PVD Seagull 3600 Movement Question

[xlr8tn]

I received a new movement today and proceeded to install but noticed that the balance works fine when facing up but when flipped over it stops by itself. The watch is fully wound. Is there anything that I can start to look at to figure out what is stopping it? I initially mounted the dial and hands and came across this so I took everything off and it is doing the same thing. I know these movements generally come from the factory unserviced, but trying to determine if I need to send it back, tell the vendor to send me another one, or try and fix it myself.

Thanks,

Brent