Total Biscuit Of Rejuvenation Bug

I've been playing Tahm Kench on Support in PBE for a while, and now in live. After playing a couple games of him in the live server, I noticed my biscuits weren't giving me the 10 mana on activation that they were supposed to, and at one point, costing my ADC partner a death as I was 8 mana short of eating him away from a certain death scenario. I believe the Health on activation was functioning correctly, but it was not granting me the 10 mana. Thinking it might be a one-time thing and that I just didn't notice it, I tried using it again several times, and each time, mana was not instantly recovered.

It's not a huge problem, but it does eliminate one of the benefits of being a support. Food items!!

Tahm loves his biscuits.. Can this please be looked into? And would someone else be willing to confirm this as well? I would like to know if this is just some strange occurance in my Tahm games or if I'm just seeing strange things..