Could problems arise if I don't properly follow the precautions after getting fillers?

While looking into fillers, I heard a lot of talk about how important post-procedure care is.

I'm wondering how much attention I need to pay to the precautions after getting fillers.

I heard that I should avoid pressing or irritating the area immediately after fillers, but I'm confused about how careful I actually need to be.

I am also curious about when I can wash my face or wear makeup after getting fillers.

I would also like to know what specific areas I need to pay attention to to maintain the filler effects for a long time. I'm worried that if I don't manage it properly, the shape might change or I might develop problems, so I would appreciate it if those of you who have taken good care of your fillers could share some tips.