Hello Team,
I created many rules to assign issues based on a custom field value when the issue is transitioned to a specific status on the workflow. The rule was created using the Smart value option as you can see on the screenshots below.
All the rules have almost the same structure the difference between them is the transition and custom field used to create the rule.
I created one rule that when the ticket is transitioned to the Design Approve status the ticket should be assigned to the user set on the Product owner custom field and the rule is working fine.

The problem I am having is that I create a similar rule but with a different custom field and the rule is not working. It actually unassigns the ticket if it is assigned.
I am not sure what could be wrong. Any ideas about what could be happening? Thank you.
