2.0TDI 2016 Octavia manual gearbox serial number ?

Hi All,

I know that the gearbox on the octy has a product code to identify the model but can anyone tell me if there is also a unique serial number please which can be traced to the original build. 

Having issues with a dealer after clutch / DMF replacement (which was a waste of time to correct noise) and noisy gearbox from cold which wasn't present beforehand (approx 60K miles). Also had leaky drive shaft seal on gearbox after work carried out though not beforehand or present on the service video. Concerned that either my gearbox main shaft bearing has been damaged or even that I've had the wrong gear box back.