Aram-Arama missions bug

So today i found out,since i havent been playing lots of league in past few days,that new missions came out,and i was interested in that last one ˝Prize magnet˝..so i sat down and did all the missions and i expected to gain a hextech chest and a key but it still said that i had 2/3 missions completed,tho i had no other missions to complete, I hope that this bug is fixed, i just want my rewards and other players not to experience the same little problems.