Could not unmount revokefs-fuse filesystem at /var/tmp/flatpak-cache-UFOYK2/org.freedesktop.Platform-FJ9MK2

[NobinPegasus]

When I try to install using flatpak install I get this error. How can I fix it?

Warning: Could not unmount revokefs-fuse filesystem at /var/tmp/flatpak-cache-UFOYK2/org.freedesktop.Platform.Locale-LEOYK2: Child process exited with code 1
Warning: Could not unmount revokefs-fuse filesystem at /var/tmp/flatpak-cache-UFOYK2/org.freedesktop.Platform.openh264-WQFQK2: Child process exited with code 1
Error: Could not unmount revokefs-fuse filesystem at /var/tmp/flatpak-cache-UFOYK2/org.freedesktop.Platform-FJ9MK2: Child process exited with code 1
error: Failed to install org.freedesktop.Platform: Could not unmount revokefs-fuse filesystem at /var/tmp/flatpak-cache-UFOYK2/org.freedesktop.Platform-FJ9MK2: Child process exited with code 1

But it works with sudo flatpak install.