[CHAMPSELECT] Cannot choose a champion within last second or two

This has been so frustrating! I always wait until the last ~2 seconds of a draft to choose my champion (I let my team know who I'm going beforehand) But in the last two patches, 5.16 and 5.17, it disconnects me when I click on the champion to select! I've lost like a total of 20 LP from this and have had to wait so long for dodging queues. I know it's not my internet because I always get less than 30 ping in game with no spikes, and I have no lag when using my browser. It has only been happening these last 2 patches. The picture above is what happens when I try to choose my champion.