Owned Champions All Shown as Unowned

I am a brand new player (level 7) and I have just logged on for the second time in the day to find all of my owned champions have reverted to being unowned. i owned Vladimir, Xin Zhao, Fiddlesticks, Garen, Master Yi and Nocturne and was planning on purchasing LeBlanc next. Garen was obtained from a shard and Master Yi was my starting champ but the others were all purchased with blue essence. These champions present as unowned in champion select (in games) as well as in the collection and I still have access to the free rotation champions. I don't know if this is just a server issue of some kind or if for whatever reason my access to my previously owned champions has been permanently or temporarily revoked forcing me to repurchase them but if at all possible I would like some more information about this and means to reverse it with potential compensation. Thank you for your time.