Cant Access Arbiter Zone

Hello,
When i click on the burning monolith nothing happens. I have all my mats to fight arbiter. This happened after my power went out when i was fighting arbiter. When it came back on i couldn't go back into the zone and beat him. lost my mats it is was it is. I got more mats to try and access the zone and now i cant even get into the area to place the mats. Please help! I would really like to beat arbiter this league it is one of the last things i havn't done. On a side note i havnt found a single citadel and am level 95 which is kind of wild. Ive had to buy the mats twice now, which is fine, but i would like to farm them if it was more reasonable to do so, but not having found a single citadel yet makes it a very big lift.
Thanks

Tonywho#6775