What should I do if I develop resistance to Botox?

I tend to get wrinkles between my eyebrows easily.

I was getting regular Botox injections between my eyebrows.

I got it because the Botox works well, but...

At some point, I feel like I developed a tolerance, and the effect is much weaker than before.

It doesn't seem to last long, and I get the feeling that I've developed a tolerance.

What should I do if I develop resistance to Botox...?