add relationship error

Hello i m follow this guide https://academy.appian.com/#/online-course-player/270dc9fc-ad42-4d30-94db-ebfcc2f39331

But on Create the Part Record Type in step 8 I have this error when I click on new relationship.

HTTP Code: 500 APNX-1-4198-000 Error Evaluating UI Expression Expression evaluation error [evaluation ID = KP48I] : Error in a!forEach() expression during iteration 1: Expression evaluation error at function a!getInterchangeableTypes [line 27]: The data source [_a-0000eada-3d9b-8000-9ba4-011c48011c48_12846-w1857] was not found

Can you help me please? Im new in appian.

Best regards!