Cannot receive email from a specific sender

[User101]

Someone sent me two emails to my btinternet.com address last week which I did not receive. They rang me wondering why I did not reply to them. They said that they were certain they were using the correct email address. This was confirmed as, while they were on the phone, I sent them an email which they received a few seconds after I sent it. They then replied to it, but I did not get the reply.
I sent them another message using an old email address ( not a btinternet.com address) which I rarely use now, and when they replied to it, I received the email without any problems.

I have checked my span folder and all my other folders, but the emails are not there.  The sender told me that they did not get any error messages such as email cannot be delivered after they sent the emails.  Any idea what has happened?

[licquorice · Accepted solution]

You have probably inadvertently blocked the sender. Check you blocked senders list and also add the sender to your safe senders list

[gg30340]

As per the above post.

Check you not blocked the email address or the @btinternet.com domain.

Log onto your BTMail account using a browser, not an email client/app, and then click on your username at the right hand side. Select "Settings" then go to the left hand side and select "Mail". Scroll down and click on "Blocked Senders". Scroll down the list until you find the one you want to unblock and select it. Click on "delete".

[User101]

Thanks.  That was precisely the problem.