Forum Discussion
What I did in my app was:
1. Create Relationship and lookup field which will give you option to select 1 option at the time - [Brand] (Text lookup field pulled from a separate table)
2. Create Field which will Capture all values selected in field Lookup field Brand - Example: [Brand_Text]
3. Create formula field which will check for already selected values and add new selected from [Brand] to [Brand_Text].
Example: [Brand_Formula] with code
If(Contains([Brand_text],ToText([Brand])), ToText([Brand_text]), ToText([Brand_text])="",ToText([Brand]), ToText([Brand]) & ";" & ToText([Brand_text]))
4. Create From rule which will copy value from selection to [Brand_Text] (See Below)
5. If you want to still have "Multi-select field" then you can use Pipeline to copy value from field [Brand_Text] to "Multi-select field"