Build fails because of the home-manager-username.service

[Tantelicek]

This is the error code it outputs

warning: the following units failed: home-manager-student.service
× home-manager-student.service - Home Manager environment for student
Loaded: loaded (/etc/systemd/system/home-manager-student.service; enabled; preset: ignored)
Active: failed (Result: exit-code) since Sun 2025-12-14 15:31:14 CET; 1min 30s ago
Invocation: 1352e34536ae405c8c1c2cb089305ce0
Process: 11714 ExecStart=/nix/store/dhrdrka72xl4nkpm2yc8ha2kpm0ssapq-hm-setup-env /nix/store/l2pi5zw2wzn1ywvxwy5l9463g40q53fp-home-manager-generation (code=exited, status=1/FAILURE)
Main PID: 11714 (code=exited, status=1/FAILURE)
IP: 0B in, 0B out
IO: 0B read, 0B written
Mem peak: 15.5M
CPU: 153ms

pro 14 15:31:14 oavm-linux hm-activate-student[11848]: - In standalone mode, use 'home-manager switch -b backup' to back up files automatically.
pro 14 15:31:14 oavm-linux hm-activate-student[11848]: - When used as a NixOS or nix-darwin module, set either
pro 14 15:31:14 oavm-linux hm-activate-student[11848]: - 'home-manager.backupFileExtension', or
pro 14 15:31:14 oavm-linux hm-activate-student[11848]: - 'home-manager.backupCommand',
pro 14 15:31:14 oavm-linux hm-activate-student[11848]: to move the file to a new location in the same directory, or run a custom command.
pro 14 15:31:14 oavm-linux hm-activate-student[11848]: - Set 'force = true' on the related file options to forcefully overwrite the files below. eg. 'xdg.configFile."mimeapps.list".force = true'
pro 14 15:31:14 oavm-linux hm-activate-student[11848]: Existing file '/home/student/.config/fontconfig/conf.d/10-hm-fonts.conf' would be clobbered
pro 14 15:31:14 oavm-linux systemd[1]: home-manager-student.service: Main process exited, code=exited, status=1/FAILURE
pro 14 15:31:14 oavm-linux systemd[1]: home-manager-student.service: Failed with result 'exit-code'.
pro 14 15:31:14 oavm-linux systemd[1]: Failed to start Home Manager environment for student.
Command 'systemd-run -E LOCALE_ARCHIVE -E NIXOS_INSTALL_BOOTLOADER --collect --no-ask-password --pipe --quiet --service-type=exec --unit=nixos-rebuild-switch-to-configuration /nix/store/ildgcval6p8nk8yiwd1jblxxz61l59x3-nixos-system-oavm-linux-25.11.20251213.28bb483/bin/switch-to-configuration switch' returned non-zero exit status 4

Description
I have made some edits to my home.nix, mostly plasma-manager stuff. And simply can't get over this problem.
I can't restart the service, reboot doesn't help either. Any ideas?