Related field save not working

In studio, we have created a “relate” field - CASES module to a NEW module we created, and have added them to the module’s layouts.
However, when I edit a record in CASES and fill out the “relate” field (NEW module), I can select the case I require, however it does not appear in the field and the data is not saved. Click the arrow to pull up a list of available objects does work.

When we are in our NEW module, we can select the CASES field, and this saves the cases related value in our new module.

Currnelty using Version 7.10.31
Sugar Version 6.5.25 (Build 344)

Any assistance greatly appreciated.

Thank you.