Automatic lock screen not activating

I haven’t seen this lately, I think it was somehow fixed during the Artful cycle.
Those still affected, consider trying 17.10 or the 18.04Beta2?

18.3 4.13.0-37-generic Mint Mate here

I have tried everything and resume from suspend-sleep never prompts for password

Hi @eromana
A failure to lock screen when resuming from suspend is not what is discussed here.
This topic is only from failure to lock screen after specified IDLE time has been reached.