Thanks for joining this thread, @ApeSoftware.

To add the contact information, let’s re-sort the customer list and then run the Verify and Rebuild Data Utilities. I can show the steps for each process.

To re-sort the information:

1. Tap the Customers menu to select the Customer Center tab.
2. From the Customers & Jobs tab, pick the customer you’re working on and right-click beside it to choose Re-Sort List.
3. When the Re-sort List window pops-up, click OK to continue.

Once done, open the customer profile and continue with what you’re trying to accomplish. If the issue persists, perform the basic data damage troubleshooting.

The Verify and Rebuild Data Utilities are built-in tools used to validate whether your file is still in good shape and fixes common errors. Here's how:

1. Navigate to the File menu to choose the Utilities tab and then select Rebuild Data.
   
2. Click OK once you see the QuickBooks Desktop Information window.
3. Create a backup copy of the file to keep a record of the transactions. 
   
4. After saving one, QuickBooks will start rebuilding the file.
5. Once completed, hit the OK button.

To perform the Verify data:

1. Go to the File menu to select Utilities and then choose Verify Data.
   
2. The program will start checking the file. Once you see the "QuickBooks detected no problems with your data" pop-up, click OK.
   

However, if it finds an issue with the file, you'll be prompted to Rebuild Now or View Errors. The Resolve data damage on your company file article will walk you through the procedure.

Go directly to the Review Last Verify/Rebuild section to proceed.

I'm sure these steps will get you back on track.  Let me know if you have additional questions or concerns. I’ll be right here ready to answer you. Have a good one.