==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release):  0.9.9
- Deployed with iRedMail Easy or the downloadable installer? installer
- Linux/BSD distribution name and version: Debian Stretch
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

I've been using the 2FA plugin with Roundcube ever since my installation of 0.9.8 earlier this year and it has been working as expected. Recently however I have been experiencing the issue of a 2FA auth code being required at every login, vs. every 30 days as selected. IOW, the 'remember me for 30 days' option was working fine, but seems to have stopped working for reasons unknown. I have cookies enabled, and this happens with multiple browsers (Firefox and IE) so it does not seem to be related to a specific local browser or setting. I can't relate any change made on the local machine or server to the problem (although I suppose it must be a result of one, just can't guess what it is.) This was with Roundcube 1.3.6 and I just updated to 1.3.8 as a result of an iredmail 0.9.9 update, but no change and the problem persists. I have tried the obvious things such as disabling and re-enabling 2FA, etc., but no change.

Any ideas where I might look?