Hi, you have been banned because your IP has been matched to one of the banned accounts, you can see this here:
https://www.skial.com/sourcebans/index.php?p=banlist&searchText=67.247.4.14&Submit=
I have just checked your connection history, and you had not logged on the last 2 days, until today. In between those days, on the 17th, somebody was caught spamming lmaobox binds, usually indicating they are using the lmaobox-hacks. That person caught also shares your IP.
It might not have been you if you aren't lying, it might have been somebody in your household sharing the same Wi-Fi. However there is no doubt about it, that it happened from your place, since you have been on that tagged IP for several months.
It doesn't look very good for you, because there is hardly no doubt it was either you or somebody in your place, and even if it wasn't you, we still have to keep that IP banned to prevent the hacker from returning.
Edit: Just noticed you have one of the banned accounts in your friendlist.
https://steamcommunity.com/profiles/76561198204824979
Probably a brother/sister or a rl friend that plays tf2 too since that person "Kingfilk" was banned too for the same reason. Probably it was him/her if it wasn't you, using hacks on your IP. But it wouldn't really change the outcome since we still have to keep that IP banned.