Patching multi-select lookup column that has existing values

[Anonymous]

Attempting to emulate this method...

PowerApps Patch Multi Select Fields  

Patch is throwing error when values previously selected but not subsequently changed, which I tracked back to blank values in collection for combo box selected items (I am showing row count and Id & Value below - I've substituted "Blank" for Blank().)...

Here is how I set table variable, and specify DefaultSelectedItems for combo box...

Here is my code to collect selected items from combo boxes (Strength = ResponseA and Weakness = ResponseB)...

Here is my code to patch existing list item...

Lookup column settings...

Any help in understanding how to fix/work around this would be greatly appreciated. 

[Anonymous · Accepted solution]

I believe I found the issue...

Noticed a mismatch between Items and DefaultSelectedItems...

Changed DefaultSelectedItems to...

Collections used in Patch now show Id & Value, even if no changes...   (and no error occurs !!)