IRS did not receive payment

[skb]

I mailed my tax return for 2017.  My return included a check for the taxes I owed.  In June the check had not cleared, but all the IRS could tell me was that my return had just been received ( I mailed it in April ).

Now in September, I received notice that "payment was not received", so I owe a fine plus interest. They can't tell me if they ever received the check or not.  

Do I have any standing to have this reviewed or do I just pay  the fine?

Thanks

[GabiU]

If you owe the IRS, you should pay. There's an option to pay online now so a mishap like that won't happen.