Unclear error message "An unhandled error occurred" when creating issue on MS teams and not filling a required field

When creating a Jira issue using the create screen presented by the integration on MS Teams' channel, if a user misses populating a value on a mandatory field, the error message is misleading :
Error
An unhandled error occurred. We are working on it.

This error occurs when the field is not required on Jira but Scriptrunner has a condition that turns the field as mandatory depends on the value selected on another field.

The add-on script was not created to run on MS teams, so the condition is not executed. The issue fails to be created on Jira.

We would expect a clear message returned to MS Teams explaining why the error had occurred (Field xxx was not filled).

Environment
Jira Server 8.5.4
Microsoft Teams for Jira v.2020.5.1
Scriptrunner add-on