I don’t understand why the sender would be sending me unspent unconfirmed btc, that defeats the purpose of have a payment sent to me with high priority.
Do you know who is the sender? I mean if you know this person? Did you deal or exchange anything with him?
If it was just a random guy on telegram maybe you are dealing with the scammer.
Some scammers do this trick by sending BTC with a very low fee and they keep sending it to their own different wallet addresses to keep their track hidden and later they are going to replace the parent transaction with a high transaction fee so that the TXID they provided to you will no longer searchable on the explorer.
Do you know this person(sender)?