dsocpa,

I am trying to replicate the scenario you are describing in your post.  I am posting a screen shot of the return.  

I think the answer to your question is to enter the $5,500 of PTE tax paid into the Information Worksheet, Part III for estimated tax payments.  This will transfer the total to line 13a and then line 15.  

This will create the overpayment you need to allow a user entry on line 18 to carryforward the amount to 2022.  

We value your input and hopefully this resolves your issue.  If not, please reach out again and we will work to find your solution.