Relic Shield Recharge Issues [Gameplay]

I play a lot of Thresh (Dark Star skin if it makes a difference), and I use the Relic Shield support item when I do so. I noticed that during the last few games that the icon that indicates the charge/recharge time for last hitting minions was not working properly. Instead of seeing the recharge timer slowly move around the box, it was just a solid color with a zero number in the bottom right corner. I wasn't too focused on it in game but I noticed that after some time it would start recharging from the beginning, forcing me to wait much longer than normal to use the item's ability.