GAMEPLAY Ziggs w ability disappearing on cast, preventing from further use of the ability.

Recently I played a game as ziggs and when I cast my w ability, satchel charge disappeared upon cast and did not work for the rest of the game. It is important to note that I was slowed by Karthus wall when it happened.

For the rest of the game it cycled between being greyed out and the ability icon that appears when the satchel charge is physically down on the rift (the highlighted version of the icon)

I could not use the ability what so ever. It also stated that the ability costs 0 mana.

The enemy team was tryn karthus rengar cait morg My team was ziggs leesin singed tristana thresh