How can I convert the optionset to a string that it can be used in the CONCAT function?
I dont know the type picklist, but here are my thougts:
Convert something to text with Text(varToConvert)
I think you can't convert a picklist into a String (but try it anyway!), because it contains multiple records of something. Try to filter your picklist with the following:
Thanks! I tried this already, but without success. It is saying "Function TEXT is not existing".
The picklist is a "Option" and I need the value which is selected.
I think actions in calculated field are limited to the fuctions listed here: Define calculated fields | Microsoft Docs
Has anyone else any idea? Or is it just not possible?
This will get the choosen value of your option field.
Let me know if this worked for you (: