i have some difficulties with an expression o...

[Valiant_Beekes]

i have some difficulties with an expression on appsheet: IF({[PRODUCT]=“539-10”},{CONCATENATE([MACHINE],"-",YEAR([DATUM]),"-",UNIQUEID())},{[MACHINE].[BATCH]})

it keeps giving the error: LIST has elements of mismatched types while the types of the columns are text.

is there someone with a solution?

Cheers, Valiant