With A11 and current twrp, you need to turn off pin and password screen lock. Pattern is ok, so best to switch to it before as you will lose face and fingerprint settings if you just switch it off.
You can wait until the OTA version comes out normally on a Saturday night and use the built in updater app or go to settings, my device and press on the number 12 to get to the updater.
Or download the ROM from the forum weekly download page and once downloaded, reboot to recovery, install, select downloaded ROM, swipe across to flash. Once done, select the wipe option presented to you and swipe right to wipe dalvik and cache only. Once done, reboot to system. Don't forget that this first boot will always take much longer as you have just deleted the cache but as long as you see 5G and then miui, all will be good, just wait.