Most inconsistent signal ever!!!!!!

We have LTE. Worst service ever. Signal is so inconsistent. We have a 25meg line which sometimes gives 5meg sometimes 10. Yet we pay for the full 25meg. We’ve moved the rooter all over the house…makes no difference. I call them to log a complaint and I’m on hold for over 40 minutes .. literally until my full months’ minutes runs out. Pathetic signal and even worse customer service