I was trying to set up my brushed tekin ESC yesterday and I tried to do the setup to calibrate and it acknowledges the neutral position, throttle but when I try to th the brake function, it doesn't beep.

When i turn it off, then back on, it acknowledges the brake by having the bottom lit when the brake is applied. anyone else have this problem?

Sounds like you need to reverse the channel. Common with the Tekins

through the remote?

I had that happen once when I had my speedo set to brushed mode with a brushless motor attached. The wrong mode or T/B endpoints not maxxed on the radio and the Tekins will refuse to complete calibration.