@Agrawal S If not allotted, money will be refunded to UPI account, not a big issue.
But if allotted shares will be credited to demat holders, that is fraud, if wrong UPI ID used. There arise problems.
By the way, from 1st Dec 2023, third party transactions not allowed as per SEBI rules.
And IMO, transactions should be restricted while applying process itself as it is done in SBI ASBA.
At present, as per rules, money is blocked, and third party transactions are liable to reject while allotment only.
Hope restrictions are implemented strictly.