Cannot open multiple ALTS

Just to give a quick summary. I just finished my Main and 3 atls for the dailies. then i switch character to my 5th alt to do the same dailies. I was able to log the 5th character in-game then suddenly i got DC’ed for unknown reason. so i thought i may be just my internet connection so i logged back in. Then when i clicked and launch the 5th alt. it seems that i am not able to log this character in. error shows as “could not connect to game” so i tried logging out of steam and relogging my account. so it shows the same.

i am able to log my 2 tier 3 characters but i am not able to log my 3 tier 2 characters now.