diff --git a/gradle.properties b/gradle.properties
index 92406a7ab..b2bc0ecc9 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -49,7 +49,7 @@ stdlibJwtVersion=2.13.0
 stdlibOAuth2Version=2.12.0
 
 # Stdlib Level 05
-stdlibHttpVersion=2.12.1-20240918-130700-9906dbe
+stdlibHttpVersion=2.12.1-20240922-195800-82c5e76
 
 # Stdlib Level 06
 stdlibGrpcVersion=1.12.0
diff --git a/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/BallerinaUtilGenerator.java b/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/BallerinaUtilGenerator.java
index 44df9074a..0019a632b 100644
--- a/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/BallerinaUtilGenerator.java
+++ b/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/BallerinaUtilGenerator.java
@@ -121,7 +121,6 @@
  */
 public class BallerinaUtilGenerator {
 
-    private boolean headersFound = false;
     private boolean pathParametersFound = false;
     private boolean queryParamsFound = false;
     private boolean requestBodyEncodingFound = false;
@@ -136,7 +135,6 @@ public class BallerinaUtilGenerator {
     private static final String GET_ENCODED_URI = "getEncodedUri";
     private static final String GET_ORIGINAL_KEY = "getOriginalKey";
     private static final String GET_PATH_FOR_QUERY_PARAM = "getPathForQueryParam";
-    private static final String GET_MAP_FOR_HEADERS = "getMapForHeaders";
     private static final String GET_SERIALIZED_RECORD_ARRAY = "getSerializedRecordArray";
     private static final String CREATE_MULTIPART_BODY_PARTS = "createBodyParts";
     private static final String GET_VALIDATED_RESPONSE_FOR_DEFAULT_MAPPING = "getValidatedResponseForDefaultMapping";
@@ -151,16 +149,6 @@ public void setQueryParamsFound(boolean flag) {
         this.queryParamsFound = flag;
     }
 
-    /**
-     * Set `headersFound` flag to `true` when at least one header found.
-     *
-     * @param flag Function will be called only in the occasions where flag needs to be set to `true`
-     */
-    public void setHeadersFound(boolean flag) {
-
-        this.headersFound = flag;
-    }
-
     /**
      * Set `pathParametersFound` flag to `true` when at least one path parameter found.
      *
@@ -260,9 +248,6 @@ private Set<String> getFunctionNameList() {
                     GET_SERIALIZED_RECORD_ARRAY
             ));
         }
-        if (headersFound) {
-            functionNameList.add(GET_MAP_FOR_HEADERS);
-        }
         if (pathParametersFound) {
             functionNameList.add(GET_ENCODED_URI);
         }
@@ -288,7 +273,7 @@ private List<ImportDeclarationNode> generateImports(Set<String> functionNameList
             ImportDeclarationNode importMime = GeneratorUtils.getImportDeclarationNode(BALLERINA, MIME);
             imports.add(importMime);
         }
-        if (defaultStatusCodeResponseBindingFound) {
+        if (defaultStatusCodeResponseBindingFound || queryParamsFound) {
             ImportDeclarationNode importForHttp = GeneratorUtils.getImportDeclarationNode(BALLERINA, HTTP);
             imports.add(importForHttp);
         }
@@ -301,7 +286,7 @@ private List<ImportDeclarationNode> generateImports(Set<String> functionNameList
      * @param memberDeclarationNodes {@link ModuleMemberDeclarationNode}
      */
     private void getUtilTypeDeclarationNodes(List<ModuleMemberDeclarationNode> memberDeclarationNodes) {
-        if (requestBodyEncodingFound || queryParamsFound || headersFound || requestBodyMultipartFormDatafound) {
+        if (requestBodyEncodingFound || queryParamsFound || requestBodyMultipartFormDatafound) {
             memberDeclarationNodes.add(getSimpleBasicTypeDefinitionNode());
         }
         if (requestBodyEncodingFound || queryParamsFound || requestBodyMultipartFormDatafound) {
diff --git a/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/FunctionBodyGeneratorImp.java b/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/FunctionBodyGeneratorImp.java
index 4030803e2..53ac6b781 100644
--- a/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/FunctionBodyGeneratorImp.java
+++ b/openapi-core/src/main/java/io/ballerina/openapi/core/generators/client/FunctionBodyGeneratorImp.java
@@ -128,7 +128,7 @@ public class FunctionBodyGeneratorImp implements FunctionBodyGenerator {
 
     public static final String MAP_ANYDATA = "map<anydata> ";
     public static final String MAP_STRING_STRING_ARRAY = "map<string|string[]> ";
-    public static final String GET_MAP_FOR_HEADERS = " = getMapForHeaders(";
+    public static final String GET_MAP_FOR_HEADERS = " = http:getHeaderMap(";
     private final List<ImportDeclarationNode> imports;
     private final String path;
     protected final Map.Entry<PathItem.HttpMethod, Operation> operation;
@@ -286,11 +286,9 @@ public void handleQueryParamsAndHeaders(List<Parameter> queryParameters, List<St
                     addApiKeysToMap(HEADER_VALUES, headerApiKeyNameList, statementsList);
                     statementsList.add(GeneratorUtils.getSimpleExpressionStatementNode(
                             MAP_STRING_STRING_ARRAY + HTTP_HEADERS + GET_MAP_FOR_HEADERS + HEADER_VALUES + ")"));
-                    ballerinaUtilGenerator.setHeadersFound(true);
                 } else if (!hasDefaultHeaders) {
                     statementsList.add(GeneratorUtils.getSimpleExpressionStatementNode(
                             MAP_STRING_STRING_ARRAY + HTTP_HEADERS + GET_MAP_FOR_HEADERS + headersParamName + ")"));
-                    ballerinaUtilGenerator.setHeadersFound(true);
                 }
             }
         }
@@ -355,7 +353,6 @@ private void addUpdatedPathAndHeaders(List<StatementNode> statementsList, List<S
         if ((hasHeaders || !headerApiKeyNameList.isEmpty()) && !hasDefaultHeaders) {
             statementsList.add(GeneratorUtils.getSimpleExpressionStatementNode(
                     MAP_STRING_STRING_ARRAY + HTTP_HEADERS + GET_MAP_FOR_HEADERS + headerVarName + ")"));
-            ballerinaUtilGenerator.setHeadersFound(true);
         }
     }
 
diff --git a/openapi-core/src/main/resources/templates/utils_openapi.bal b/openapi-core/src/main/resources/templates/utils_openapi.bal
index c932affd7..9e15748a3 100644
--- a/openapi-core/src/main/resources/templates/utils_openapi.bal
+++ b/openapi-core/src/main/resources/templates/utils_openapi.bal
@@ -200,12 +200,13 @@ isolated function getEncodedUri(anydata value) returns string {
 # + encodingMap - Details on serialization mechanism
 # + return - Returns generated Path or error at failure of client initialization
 isolated function getPathForQueryParam(map<anydata> queryParam, map<Encoding> encodingMap = {}) returns string|error {
+    map<anydata> queriesMap = http:getQueryMap(queryParam);
     string[] param = [];
-    if queryParam.length() > 0 {
+    if queriesMap.length() > 0 {
         param.push("?");
-        foreach var [key, value] in queryParam.entries() {
+        foreach var [key, value] in queriesMap.entries() {
             if value is () {
-                _ = queryParam.remove(key);
+                _ = queriesMap.remove(key);
                 continue;
             }
             Encoding encodingData = encodingMap.hasKey(key) ? encodingMap.get(key) : defaultEncoding;
@@ -230,22 +231,6 @@ isolated function getPathForQueryParam(map<anydata> queryParam, map<Encoding> en
     return restOfPath;
 }
 
-# Generate header map for given header values.
-#
-# + headerParam - Headers  map
-# + return - Returns generated map or error at failure of client initialization
-isolated function getMapForHeaders(map<anydata> headerParam) returns map<string|string[]> {
-    map<string|string[]> headerMap = {};
-    foreach var [key, value] in headerParam.entries() {
-        if value is SimpleBasicType[] {
-            headerMap[key] = from SimpleBasicType data in value select data.toString();
-        } else {
-            headerMap[key] = value.toString();
-        }
-    }
-    return headerMap;
-}
-
 isolated function createBodyParts(record {|anydata...;|} anyRecord, map<Encoding> encodingMap = {}) returns mime:Entity[]|error {
     mime:Entity[] entities = [];
     foreach [string, anydata] [key, value] in anyRecord.entries() {