RE: I cant select Position Lookup Field value
Hi Onur,
It’s so strange, I have added the position lookup field in the form, it can be selected.
1.You can check the field is read-only or not.
Go Settings > Customization > Customize the system > Entities > forms to double-click the position field to open ‘Field Properties’ dialog.

2.check field security for the field.
Go Settings > Customization > Customize the system > Entities > fields to click position field.
Make sure the ‘field security’ is disable.

if not, you need go Settings > Security > Field Security Profiles to check which record can't allow create and update the position field.
then click teams and users to view who has been added, if they have selected, they can't edit position field.

Regards,
Leah Ju
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