For GDM3 - what does your login manager look like? If it looks like this then you are using lightdm/slick greeter
For GNOME-Shell - start at this part of the thread Lockscreen not working after update to 21.10 - #12 by fossfreedom
Related Topics
| Topic | Replies | Views | Activity | |
|---|---|---|---|---|
| Screen lock doesn't work after upgrade to 21.10 | 2 | 786 | October 20, 2021 | |
| Lock screen no longer works after 22.04 upgrade | 14 | 6910 | December 24, 2022 | |
| Lockscreen not working after update to 21.10 | 40 | 7479 | May 30, 2022 | |
| Screen blank settings not working | 5 | 2725 | May 26, 2022 | |
|
23.04 - Screen Lock
|
9 | 1208 | April 19, 2023 |