Most likely your shoes don't fit and you should try another size. Are you wearing through the outside first or the inside first?

You just have to be on your toes.

So I searched a bit and this link has a few suggestions: https://www.blister-prevention.com/blogs/prevention/holes-in-the-back-of-my-shoes

TL;DR you can have a deformity on your feet called Haglunds which can worsen wear on the heel counter. There is also a possibility that you can relace your boots or use padding to reduce wear.

Either wrong size, gait or your heel is pronounced.

Try different sizes as others described otherwise you can buy stickers you put on the inside.

Or buy shoes with leather counters.

I had to read that link to learn what a counter is.

It might be that your foot heel is unusually prominent. I'd be trying a gel cushion or pad on the inside of the shoe, which you could replace if worn out.

Double layered anti-blister socks.

That happens to me with padded structural sneakers. I switched to shoes that aren't structural (Nike Flyknit, Merrell vaporglove) so the soft fabric of the shoe moves with my foot and hasn't happened since.

The leather counter in dress shoes also seems to be more durable as others have said.

I also wear through the inside fabric quite fast but I also wear my soesea little bit on the loose side. Maybe try a different size or cut?