Try https://myaccount.google.com/device-activity and sign out of the devices you lost.
I have had two tvs stolen in the last 2 years. Both tvs have all my streaming info - Netflix, Amazon Prime, Hulu and YoutubeTV. Today I received an extraordinarily high bill from HULU and called to find out what happened. Apparently my stolen tvs are now being used and because I had never changed the password after the thefts, the thieves can not only use my stolen tvs, they can use all the streaming channels I'm paying for. I immediately began changing passwords. The problem is, that despite changing my password multiple times via google for my youtube tv, my tv remains signed in. As does my fiance and son's (I have a family plan with me as the manager). I have been on the phone with Google for an hour and they told me how to go in to my google account and check my devices. Only my laptop and iphones show up - none of the three tvs I've installed youtube tv on, nor the tv of my son or fiance. I was told to click on the link that says "don't recognize a device" and that by going through that process, it would disconnect all devices on my account and require a new sign in with the new, updated password. Problem is, I can still access youtube tv from my tv and haven't been asked to update any credentials - meaning the thieves can continue to use my youtube tv because those tvs will likewise remain signed in despite the fact that I've changed the password twice now. Google doesn't seem to have a clue what else to tell me. I hate to have to cancel my subscription over this but I refuse to continue to allow thieves to steal from my (I pay $50/month for youtube tv!). I've tried turning my tv off and then on again and I can still access youtube tv without having to sign back in. Does anyone here have more knowledge than google and their google tv team seem to have? They truly don't have a clue on how to fix this security issue.