Bitcointalk Account Strange Email Added?

[7788bitcoin]

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Of course, if you use a valid email address, it will be confirmed but if you use an invalid email during account registration and a message is sent to that email address without delivery, it will automatically reset to something like this -- u3587264@bounces.invalid. When i registered my username i used an invalid email address but after some time i sign up the email address on google mail and it became valid.

That is not always true, I have been using a valid email address for years, but last month I noticed that it changed to @bounces.invalid and I re-entered the same mail address again which I was using with this profile and my profile was showing that I changed the mail address and even the system logs report that it is a changed mail address. 

[Cryptohygenic]

My advice is to follow his recommendation and replace that address with a valid one of yours.

Yes, to fix the error or to treat the threat Op or anyone in similar situation can just change the email as soon as possible before the other party denies you the access since you still have access to the account and then put your own valid and verified one to keep your privacy secured.
At same immediate effect, also change your logging password before the hacker denies you access to the account.

[OcTradism]

Yes, to fix the error or to treat the threat Op or anyone in similar situation can just change the email as soon as possible before the other party denies you the access since you still have access to the account and then put your own valid and verified one to keep your privacy secured.
At same immediate effect, also change your logging password before the hacker denies you access to the account.

Changing something for account security is good like what you already recommended: change the email address, change or use a strong password for the email, change 2FA of that email account, change to a strong password for forum account.

There is another thing to do for securing the account: signing a Bitcoin message from private key that you own and stake that message and the Bitcoin address in this forum.

Stake your Bitcoin address here.

If possible, let's do staking your PGP key.
The BCT PGP/GPG Public Key Database: Stake Your PGP Key Here.

Generally for security, privacy and account recovery.
Forum account: security, privacy, and recovery
Security and Privacy Encylopedia.