Shutdown takes very long time in full disk encryption

Hi, my system suddenly started to take a long time to shutdown starting today.

When I used shutdown from the GUI (gnome) or the systemctl poweroff, it took around 2 minutes before the system to fully power down. It will hang at the blank screen with a blinking cursor, no other text there at all.

This is my journal from one of the shutdown attempts.

– Journal begins at Mon 2021-04-26 16:30:54, ends at Tue 2021-04-27 23:58:28. –
23:55:15 gdm[526]: Gdm: Failed to list cached users: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name :1.9 was not provided by any .service files
23:55:15 nextdns[523]: Deactivate: NetworkManager resolver management: exit status 4
23:56:46 systemd-cryptsetup[3047]: Device luks-c3ef4558-c851-4bb5-a76e-6e552efea217 is still in use.
23:56:46 systemd-cryptsetup[3047]: Failed to deactivate: Device or resource busy
– Boot f0e34d309ee84bb7afcdd60af7c76af1 –

The process seemed to hang at the systemd-crypsetup (it took at least 90 seconds from the journal).

My spec: AMD Ryzen 5 3600, nvidia 2080 super, Ram 32 GB, Kernel: 5.11.16-arch1-1, SSD Force MP510 NVMe 500 GB (full disk encryption at installation)

I installed EOS only around 2 days before, and there was no delayed until now. I didn’t recall any significant update or weird config that I did to the system, it just seems to suddenly happen today.

Does anyone also encounter this problem or know how to fix it?

Thank you.