Professional tax notice

Hello,

My wife is running a small business of 3D printing services in Pune. She is registered under GST and does not have any employees working.

She has recently received a notice regarding Registration under Profession Tax Act 1975 (PTRC / PTEC).

Is this registration mandatory after registering under GST?

Also do she need to get the shop act license if no employees are employed. And where to intimate about the no of employees if less than 10?

Please guide us for next due course of action.