I have sold digital goods to a unknown person. They have sent me a Zelle transfer to my Bank of America account of 2,000. The money has been credited to my account and has became available. Although this is true, it has remained as "processing" until the next business day.

Is there any way a bad person on the other end can cancel the processing money? or (as i am aware) does the money leaves their account when they send it and immediately lose it.

I want to be sure the transfer has cleared before selling more digital goods to them.