As someone who went through the same process, including using a Huawei watch previously, I encourage you to try Autosleep. It has much better sleep detection magic and exposes a few knobs that enable you to fine-tune the autodetection and also manually correct the sleep records in sensible ways.

It integrates with Health, so it has the bonus of tidying up the sleep data all across the board.

Not related to the developer in any way, just a very happy user.