MS is common to both forward and reverse so since you had one mode working that one must be ok.
MS1 and 2 are the forward and reverse contactors. So either one of those was defective/miswired or one of the coils was not getting power
On the MS1 and 2 contactors the power comes in at the top and out at the bottom so you would need to probe with your meter on AC volts and see which one is not showing voltage on all the bottom U and V and Z terminals when energized
It's possible the problem is just a corroded or broken wire or loose terminal screw- that's why you want to pinpoint the problem first with your voltmeter.
Especially important when you are working without a schematic diagram