PJB - Contract-->>Parties tab-->>Customer is updated and "Update Lines" is giving error

Summary:

Content (required):

Contract is created with Customer A (Parties tab -->>Contact section is blank), Bill plan (bill to and bill contact is provided) and revenue plan is created and approved and active. No Invoice or revenue is created yet.

Contract is amended, Parties tab -->> Customer is updated with Customer B. In Account section, Bill to and Ship to updated. Saved.

Click on "Update Line", getting error - You must complete the required fields.

This is happening for all customers (old and new) and all PODs.

Version (include the version you are using, if applicable):

23C

Code Snippet (add any code snippets that support your topic, if applicable):