You'll need to add the Ultimate Suite installation folder to exclusions.
Double-click Exclude files and paths from Attack Surface Reduction Rules:
Tick Enabled and click Show:
The folder to be added may be either
C:\Users\[USER_NAME]\AppData\Local\Ablebits\Ultimate Suite for Microsoft Excel\
C:\Program Files (x86)\Ablebits\Ultimate Suite for Microsoft Excel\
Note. If you changed the default installation folder during the installation, add that specific folder.
Note. If there are VBA macros in Excel files that you compare, you'll have to add these workbooks to exclusions as well. For this, copy and paste the path of the workbooks the same way as you did for Ultimate Suite. Into the Value field, enter "1". If the workbooks are saved to Desktop, simply enter "Desktop" into the Value name.