All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
Eating qaat is something upon which there is a difference of opinion among the scholars ; some prohibited it and some are of the view that it is lawful. However, we in Islamweb are of the opinion that it is forbidden as we already clarified in Fatwa 88984.
Therefore, you must quit working in Qaat and look for another job that is not doubtful. However, in case of necessity or dire need, you may earn your living from it until you find another (permissible) job.
Allaah Knows best.