Do you recall the brand of the tincture? There are various types of tinctures that could be used for insomnia. If we knew the name of the manufacturer, we may be able to provide some more assistance!
Your local dispensary might have tinctures that aren’t specifically advertised for sleep but may still be good for sleep anyhow. I would look into tinctures that have some (but not too much) CBD, a fair amount of THC, and some CBN ( if available). This combination of cannabinoids should be helpful for sleep as well