Unable to update Multi-Select field in another form

Unable to update Multi-Select field in another form

 Hello

I have the following code in the "Edit - On Success" event of my frmCountry_Market form:

for each recP in frmPlayer  [Market.contains(input.Market_WithCCode_before_edit)]
{
    newList = {"item1", "item2", "item3"};
    info newList;
    recP.Market = newList;
}




One recP record is found (the list newList is displayed in a log message).
'recP.Market' can not be set. This is what the log says:

"Unable to update data on the form variable null"

I tried updating another field in the same form (recP.Name = "Test-Name";). That worked.
I am puzzled. Any help would be greatly appreciated.

Filip