Higher API call consumption calculated than performed

[OozmaKappa]

Dear Marketstack team,
I have signed up for your free Plan to test out your service. It looks very promising. The limit of 100 calls per month is very tight, but manageable for test purposes IF it would be counted correctly. Unfortunately, the dashboard calculates more than 20 calls when I perform just 3-5. Is there a specific reason for such miscalculation? How can I use your service without being blocked after a few calls? I understand that the paid plans offer higher rates, but how can I scale my application using your service, if it charges me 5 times more than I consume?!