TypeError: Cannot read properties of null (reading '_id')

[yahyo7]

I am getting below error after I run build and start the server. web running and after I sign up/or sign in, I am getting black page with below error:
TypeError: Cannot read properties of null (reading '_id')
at dg (index-CFb0_dR-.js:243:7512)
at Ba (index-CFb0_dR-.js:38:16961)
at sh (index-CFb0_dR-.js:40:43789)
at rh (index-CFb0_dR-.js:40:39575)
at o0 (index-CFb0_dR-.js:40:39503)
at Vi (index-CFb0_dR-.js:40:39357)
at Ho (index-CFb0_dR-.js:40:35753)
at gc (index-CFb0_dR-.js:40:36554)
at cn (index-CFb0_dR-.js:38:3258)
at index-CFb0_dR-.js:40:34095

[yahyo7]

solved:
missed some ? when defining user(?).smth

[suraj-khot-19]

Always use ? Before using any of the field from user like =>
user?._id