I bought it at level 1, and leveled it to 15. Now when I go to gift someone I get an error along the lines of 'a careless yordle knocked something important, gifting.. blah blah", but when I try to gift on a different account it gives me the regular screen.

Does riot know? Has this happened to anyone else? What do I need to do?

 

Wrong section - consider moving to League of Legends discussion.

And have you made sure the account is on the correct region?

 

Yes. I think it might be that the account i'm gifting is in low priority queue, because I tried to gift a different account and it went through to the regular screen.