No return receipt. Nothing on where’s my return.

I had to mail in my taxes in to the Kansas City irs address. I used certified mail with tracking and return receipt on February 3. No return receipt has been mailed back. The tracking shows that it was in transit but nothing else. I talked to the people at the post office. They don’t know anything . Should I call the irs to see if they received it? What the hell is going on? My state taxes were received and I got that return receipt.