Only hot water out of tub

I have a Moen Posi-Temp Pressure Balancing Valve. New construction. I can only get hot water out of the tub spout and shower head. I know I have cold water to the bathroom as I have it at the sinks. Could the cartridge perhaps be plugged? Any advice on how to proceed? Thanks,

Balancing spool may be siezed. Remove cartridge and shake (longitudinally)until pressure balancing slug moves freely. Reinstall.