pam-u2f: `sudo` auth does not work when requiring PIN

/etc/pam.d/sudo contains

auth		sufficient	pam_u2f.so	cue

Run command below:

$ pamu2fcfg -umaximbaz > ~/.config/Yubico/u2f_keys

Then sudo -s will work as expected, it will print “Please touch the device.”, I touch it and I get sudo access.

Now do the same, but require PIN:

$ pamu2fcfg -umaximbaz -N > ~/.config/Yubico/u2f_keys

Running sudo -s:

1. First it asks “Please enter the PIN:”, I enter it.
2. Then the message “Please touch the device.” appears.
3. Instantly Yubikey stops flashing and I get the next message: [sudo] password for maximbaz:

In journalctl I see this:

sudo[1235117]: pam_unix(sudo:auth): conversation failed
kernel: audit: type=1100 audit(1583694800.396:4001): pid=1235117 uid=1000 auid=1000 ses=1 msg='op=PAM:authentication grantors=? acct="maximbaz" exe="/usr/bin/sudo" hostname=? addr=? >
audit[1235117]: USER_AUTH pid=1235117 uid=1000 auid=1000 ses=1 msg='op=PAM:authentication grantors=? acct="maximbaz" exe="/usr/bin/sudo" hostname=? addr=? terminal=/dev/pts/7 res=fai>
sudo[1235117]: pam_unix(sudo:auth): auth could not identify password for [maximbaz]

I’m on Arch Linux, latest master (https://github.com/Yubico/pam-u2f/commit/89412d932a24617ba6bb776988805dfbe663f795), YubiKey 5 Nano

Let me know if I can help with something, happy to help investigating.