Weak mustache

This may be a dumb question but I hope that someone could help me.

I’m 21 almost 22. I know I’m young, but my beard is not very full. Middle of the chin has holes but the sides are great (still with holes though), mustache is very weak and overall I have a lot of holes.

I know that I’m still young and my beard can still massively thicken. My worry is that I’ve used Minoxydil for like 4-5 months like once a day or once every 2 days. I didn’t see much results, especially on the mustache. If Minoxidil doesn’t work, does that mean I’ll never have a beard or mustache? Any tips?

Thank you !