Any entites you summon with /summon that has a custom UUId won't be killed by the kill command.
Comments 2
This ticket is incomplete without the requested information, no response has been received within a reasonable time and we are assuming the issue has been resolved. If you are still experiencing this issue, we can reopen it at your request.
Please review the guidelines before reporting issues.
What are the exact commands you used for the summon and the kill?