Error when updating fonts

[ErnWong]

Dec 18 20:09:49 NixOS hm-activate-nixos[60453]: Existing file '/home/nixos/.config/fontconfig/conf.d/10-hm-fonts.conf' is in the way of '/nix/store/b8ab4iggkz3hnh3g25rslmxrn7jlbdwg-home-manager-files/.config/fontconfig/conf.d/10-hm-fonts.conf'
Dec 18 20:09:49 NixOS hm-activate-nixos[60453]: Please move the above files andtry again or use 'home-manager switch -b backup' to back up existing files automatically.
Dec 18 20:09:49 NixOS systemd[1]: home-manager-nixos.service: Main process exited, code=exited, status=1/FAILURE
Dec 18 20:09:49 NixOS systemd[1]: home-manager-nixos.service: Failed with result 'exit-code'.
Dec 18 20:09:49 NixOS systemd[1]: Failed to start Home Manager environment for nixos.
warning: error(s) occurred while switching to the new configuration

[ErnWong]

dotfiles  main 「𝚫 ⟫4 」  ⎔
✖1 ❯ diff -u /nix/store/b8ab4iggkz3hnh3g25rslmxrn7jlbdwg-home-manager-files/.config/fontconfig/conf.d/10-hm-fonts.conf /home/nixos/.config/fontconfig/conf.d/10-hm-fonts.conf
--- /nix/store/b8ab4iggkz3hnh3g25rslmxrn7jlbdwg-home-manager-files/.config/fontconfig/conf.d/10-hm-fonts.conf   1970-01-01 12:00:01.000000000 +1200
+++ /home/nixos/.config/fontconfig/conf.d/10-hm-fonts.conf      2021-12-18 19:47:07.662401251 +1300
@@ -1,16 +1,13 @@
 <?xml version='1.0'?>
-
-<!-- Generated by Home Manager. -->
-
 <!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
+<!-- Generated by Home Manager. -->
 <fontconfig>
-  <include ignore_missing="yes">/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/etc/fonts/conf.d</include>
-  <include ignore_missing="yes">/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/etc/fonts/fonts.conf</include>
-
-  <dir>/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/lib/X11/fonts</dir>
-  <dir>/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/share/fonts</dir>
-  <dir>/etc/profiles/per-user/nixos/lib/X11/fonts</dir>
-  <dir>/etc/profiles/per-user/nixos/share/fonts</dir>
-
-  <cachedir>/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/lib/fontconfig/cache</cachedir>
+ <include ignore_missing="yes">/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/etc/fonts/conf.d</include>
+ <include ignore_missing="yes">/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/etc/fonts/fonts.conf</include>
+ <dir>/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/lib/X11/fonts</dir>
+ <dir>/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/share/fonts</dir>
+ <dir>/etc/profiles/per-user/nixos/lib/X11/fonts</dir>
+ <dir>/etc/profiles/per-user/nixos/share/fonts</dir>
+ <cachedir>/nix/store/iyr5z0mapp62fxgi9ab9qm7n5lzn13w3-home-manager-path/lib/fontconfig/cache</cachedir>
+ <dir>~/.local/share/fonts</dir>
 </fontconfig>