FortiClient 7.4. no OTP pop-up window

I have installed FortiClient VPN 7.4.01658 (no license) on Windows 10 22H2 and configure an IPSec VPN with password+OTP (hardware) using FortiGate 7.4.4 (RADIUS client) and FortiAuthenticator 6.6.2 (RADIUSe server and LDAPS) .

For users without FortiToken assigned the FortiClient is working as expected.

For the users that have FortiToken enabled, the FortiAuthenticator is requesting the token but the FortiClient does not pop-up the windows to insert the OTP code.

This setup worked before, for 10-15 times, popping-up a small window to insert OTP code but suddenly stopped working.

No changes were done during this time on the Windows level.

The Microsoft Visual C++ 2017 Redistributable, found on the FortiClient Tools package was installed.