This only happens on linux not windows.

where do you give data to contex?

Well since you cropped out the line numbers, I'd say either change your 'User not found' error to something that's more distinguishing from internal errors... or you could just check to see if that error you're throwing is on line 180. If it's not you're likely not passing it into the write place, but if it is I'd check different cache's that might exist in the windows environment and not the linux env.

in a service file

YOu can assume that this returns the user object

The error is in AuthContext line 180, you can use console.log in fetchUser function to make sure it works as expected and then continue the flow of code to find from where user became undefined