I would check that it’s a literature recommended dose. Melatonin, for patent reasons at least in the US from what I’ve read, often comes in amounts many times larger than what is produced endogenously. May be a bit late at this point but the dose recommended by actual data may also work well and not give any side effects like making someone totally dependent on it. I mean it doesn’t seem to be harmful even in these larger Doses, but I know it can be annoying to depend on something all the time.

Looked it up, the dose it’s supposed to come in based on the data is about 1/3 of a mg or 300mcg. Many come in about 3-5mg which is obviously many times more than that.