Can't Edit Lookup Field Dropdown Selection

Can't Edit Lookup Field Dropdown Selection

I have an application with three tables: one table has two Lookup fields which reference the other two tables.

When I create a new record, the two Lookup field dropdown lists have two and eight items, respectively, mirroring the number of records in the two other tables.

If I attempt to then edit the new record, the two Lookup dropdowns are populated only with the item numbers originally used for creating the record, not with the entire list of possible selections. All other fields are editable.

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