Steps to reproduce:
- deploy a process that contains an external task
- start an instance of that process
- set external task retries by executing the following request (see ):
- The retries are set to 0.
- An incident is created.
- The response status code is 204.
- The number of retries is checked, when it is set to null, then a "Bad Request" (status code 400) is returned.
- The retries are not changed.
- No incident is created.
The same is valid for "Set Retries For Multiple External Tasks Sync/Async"  and .