Spektrum ESC flashing red light and not working

This is with a Traxxas Slash car and the stock receiver and Spektrum Firma 85A Brushless Smart ESC. Perhaps this speed controller does not work with stock Traxxas receiver?
This is in a Traxxas Slash 2wd car.
I figured out the problem! The ESC needs to be plugged into channel 3 of the receiver for some reason. 1 and 2 are for steering in the case of this receiver.

[@kevinlieb]

My mistake: I needed it on channel 3 of the receiver, not channel 2. Its fine now!

[@cherokeenation1776]

Yes, channel three is for the ESC. I have the 85amp 4000kv motor combo on my slash and it works great. Probably 40+mph. Its super fun.

[@martinbullla7654]

Did You calibrate the throttle by holding down the set button and powering on the esc Wait for it to start beeping, press the set button while the trigger is at neutral, it will beep once pull the trigger full throttle. It will beep twice, put it full reverse. It will beep 3 times release the trigger. It will beep and it will be set power it off power back on, it's calibrated.

[@reggygoff4173]

Have you figured yours out? I’m having the same problems

[@PinKomlet]

I’ll try what the first comment says. I have the same issue my man. Just bought it a week ago