When you turn on your blinkers they work fine until you hit the brakes then the blinker stops blinking and stays on how do you fix this?

You might want to try replacing the bulbs in the tail lights, could be a short in the bulb or possibly a bad ground connection

You have installed a single contact bulb (possibly an 1156) into a brake light socket meant for a dual-contact bulb. The single contact bulb is shorting the two contacts in the dual-contact socket.

The Fix: Replace the improper single-contact (single filament) bulb with the proper dual-contact (dual-filament) bulb. Dual filament bulbs are typically used in brake lights. Look there first.