Hi @Anonymous ,
Based on the formula you provided, I think you have some misunderstanding with above formula.
When you use Patch function inside the ForAll function, you should reference values from the collection for the columns in your Patch function rather than reference values from other place.
More details about the Patch function and ForAll function, please check the following video for more details:
https://www.youtube.com/watch?v=MclJ_O9HvJQ
Please modify your formula as below:
ForAll(
BesucherCollection;
Patch(
Besucher;
Defaults(Besucher);
{
Title: BesucherCollection[@ID]; /*<-- If you type ID directly here, PowerApps could not recognize the ID column is from Besucher SP list or the BesucherCollection */
...;
...;
FirmaBes: BesucherCollection[@firmabes]
}
)
)
Please take a try with above solution, then check if the issue is solved.
Best regards,