As mentioned by others, please check if the address is right or nah
Because if it's correct, then your transaction was likely flagged by their system hence, "rejected". No worries though since they typically just send it back to an address of your choice or to the address where the money came from.
You'll find similar stories in r/CashApp, for instance:
I had a deposit from my bookie.ag of BTC go to my cash app account like I've done several times and this time cash app received it then rejected it, telling me I would have to do a reversal back to my wallet.
Try checking your email or getting in touch with the support again.