64-character password works on one OpenVPN instance but do not work on another instance on the same pfSense machine

[batng]

Hi,

I created an OpenVPN server instance on the pfSense machine, added a pfSense user via WebUI:
System->User Manager, set the password to 64 characters and I was able to log in remotely to OpenVPN and everything worked great.

Then I created another OpenVPN server instance on another port and wanted to connect with the same username and password and I was constantly getting authentication error on OpenVPN client.

I was very confused and after some time I decided to try a shorter password. I set it to 52 characters and it started working for log in to both OpenVPN server instances.

I understand that there might be a limit of oficially supported password length for OpenVPN+pfSense? Is that a case?
If so, what is the maximum supported password length?

But if it is so, this should be consistent and the password length should be handled in a way that every OpenVPN instance will handle it the same way (either allow log in or reject it with authentication error).

Has anyone come across such a problem?

pfSense version:
Version 2.4.4-RELEASE-p2 (amd64)
built on Wed Dec 12 07:40:18 EST 2018
FreeBSD 11.2-RELEASE-p6

openvpn-client-export version: 1.4.18_3

Thanks for help!