Just to confirm, are you still able to sign into YouTube? If yes, we suggest adding extra layers of security to your account w/ these tips: https://yt.be/help/XEbn If no, have you tried following these steps to regain access to the account: https://yt.be/help/nr5L ?
@TeamYouTube My channel was stolen. Someone stole my channels without my permission. Please help me. How do I know if I can contact you? I can prove to you that the channel is mine. Please tell me your e-mail address and I will contact you. Please help me. 

pic.twitter.com/NqdZ8Xr3s9
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