I am not always receiving the end-call-report What can be the reason?

it may be due to an unselected end-of-call-report in server messages, webhook misconfiguration (URL, headers, response), short or failed calls, assistant misconfigurations, or network and rate-limit issues.

end-of-call-report is definitely selected, and webhook is most likely ok (as usually end-of-call is received) It can be indeed due to short or failed calls - there is sometimes eleven labs pipeline error. And sometimes I test calls shortly. So, how do I handle those?