If I give a check in payment of an obligation or purchase and the check never cleared. The recipient never called me to say he lost it or misplaced it. Do I have to call the recipient and give him another one?
There is a discussion of this topic here.
Summary: There is no obligation for a buyer to inquire after a seller regarding why a check has not been cashed. However, if the seller confronts the buyer to request another check, then it depends: If the original check is ruined or expired, the buyer has an obligation to write another check. If the original is lost, the buyer may refuse to repay.
I am no expert, so I do not know what the halacha says about this. But I believe that common decency would require you to at least call this person and discuss the matter.