Blitzcrank Bug (P v AI)

I was playing a game against AI's playing as Blitzcrank support helping my friend learn MF. We were going against Graves/Morgana. When we got to the inner turret pushing into the enemy base, I went to grab Graves and he got stuck on the turret. There was no shield, etc. on Graves, I was trying to pull him through the turret but once he reached the turret he got stuck. (Didn't take a picture because it happened too quickly :/)