Hi @waasthissen,
Try this as follows, it should solve your issue:
In the survey tab of your xlsform:
In the choices tab of your xlsform:
In the settings tab:
Data entry screen as seen in Enketo:
Reference xlsform:
aSks7cvxusQe6QkLZy9V2R.xlsx (11.9 KB)
Have a great day!