How to make delete endpoint in phabricator?

Question

sorry before i am a newbie person to use phabricator and i have a task to make a delete endpoint to delete transaction comment.

I've tried to make the same as deleting the flag, but still not working.

$this->attachHandleToFlag($flag, $request->getUser());
$ret = $this->buildFlagInfoDictionary($flag);
$flag->delete();
return $ret;

do i can make a delete endpoint for transaction comment? how i do that?