Victor SP Failing to Calibrate

I recently bought 4 Victor SP motor controllers and have been trying to calibrate them. I’ve followed the spec sheet steps but they are failing to flash green (pass calibration). I’m sending a PWM signal with a period of 20ms with max and min duty cycles as 2ms and 1ms respectively. I’ve tried multiple tweaks but they don’t seem to calibrate. Testing the default calibration yields a deadband around 1.65ms with min and max, 0.68 and 2.4 (which seems correct with the spec sheet). Any advice would be much appreciated. Thank you.

This forum is for the VEX IQ, and may not be the correct place for this post.