I just submitted a ticket (#4417990 to be exact) explaining, in detail, the "disappearance" of numerous champions and skins from my account. My patience is running slightly thin today, so someone please look in to this at their earliest convenience!!!
Thank you for bringing your concern to the Help and Support Forum! After reading your thread, I went ahead and investigated the Ticket Number that you have provided in your message. It appears that you did receive a response from one of our Player Support Specialists shortly after originally submitting your ticket.
After reviewing this response, I went ahead and performed an additional audit of your account to confirm that this content was properly re-added to you. If you believe that any champions or any other content is still missing from your account, please do not hesitate to let us know by replying in your original ticket!
I do deeply apologize for any inconvenience this issue may have caused!
Best of luck upon the Fields of Justice!