[NoMethodError] empty not defined for server ID integer

[mminer4]

I'm trying to send a basic email from a local app and keep running into an error with the validation of the server ID number. The documentation is clear that it should be an integer, but the validation function is failing on the empty check. Here is the stack trace, with my server ID changed to a nonsense integer.

Traceback (most recent call last):
        5: from email_test.rb:21:in `<main>'
        4: from email_test.rb:18:in `send_basic_email'
        3: from /home/matthew/.rvm/gems/ruby-2.7.5/gems/socketlabs-injectionapi-1.2.1/lib/socketlabs/injectionapi/socketlabsclient.rb:44:in `send'
        2: from /home/matthew/.rvm/gems/ruby-2.7.5/gems/socketlabs-injectionapi-1.2.1/lib/socketlabs/injectionapi/socketlabsclient.rb:83:in `send_basic_message'
        1: from /home/matthew/.rvm/gems/ruby-2.7.5/gems/socketlabs-injectionapi-1.2.1/lib/socketlabs/injectionapi/socketlabsclient.rb:141:in `validate_message'
/home/matthew/.rvm/gems/ruby-2.7.5/gems/socketlabs-injectionapi-1.2.1/lib/socketlabs/injectionapi/core/send_validator.rb:47:in `validate_credentials': undefined method `empty?' for 123:Integer (NoMethodError)