Screen Not Locked After Waking Up From Suspend

My PC’s screen is suddenly not getting locked after waking up from suspend. I’ve been using UM 18.04 since it got out, and at first I didn’t face this type of problem.

This has been happening for about a week. What might’ve caused this behavioral change? It worked perfectly before…

I found some old thread here, but none of them seem contain any definite solution.

Any help will be much appreciated. Thanks in advance.

same thing happening. usually after connecting an external screen on hdmi, i get notifications that the ‘mate-menu’ crashed and then it stops going to sleep, and if it does go to sleep, then there is no password required for resume. I’ve been upgrading since 16.04 lts. Seems related to this post: Lockscreen bypassed by connecting external monitor on HDMI

I haven’t done anything like that… :confused: The problem started for no apparent reason!