Headless login stops working

I have set up a Kirby installation with the KQL plugin (headless) and I am consuming the data through the api/query on a separated frontend. It works properly without any errors for some time until it does not, showing “Invalid Login” error code 403.

Doing several tests I realized that if I replace the accounts from Kirby folder located on the server with the one I have from the same site in my local environment it starts working again.

Is Kirby detecting too many logins and therefore disabling the user account? or am I missing something?