There is a documentation update in flight for the helper libraries and another for OH scripted automation. This information is included.
You aren’t really restarting the timer, but creating a new one. After a timer starts it’s action, it’s terminated. There is no builtin module that provides recurring timer functionality and I don’t see any issue with what you are doing.
BTW, when posting code or logs, please put them in code fences. And welcome to the forum!