BlockBee API callback issue (Laravel 9) -- 2

I am having some issues trying to integrate the BlockBee API into my Laravel application. So far, the request to generate a BlockBee payment page works, however, the callback received thereafter is one I cannot get to work.

BlockBee Libraries:
https://blockbee.io/libraries/

BlockBee Documentation:
https://docs.blockbee.io/

Please check it before give accept the job.