That popup happens on every return that has RRC on it, its a program bug.

https://proconnect.intuit.com/community/proseries-tax-news-updates/discussion/proseries-2020-produce...

Im only guessing here, since you didnt provide a complete set of facts.....sounds like your client DID get the RRC advance issued to them but you indicated that they never received it so IRS corrected their refund.   You'll probably want to initiate a trace using Form 3911, if you google 'AARP missing EIP' it gives instructions to fill out the 3911 for a missing stimulus payment.