I assume the fault is not receiving from a specific sender or email domain? What email domain is that - just the part after the @ symbol in their email address?
If you're relying on Auto forwarding to forward every email to Gmail then don't. If the original email does not permit other senders to send email on their behalf, and that includes auto forwarding, then that mail will not be authenticated as genuine and your mailbox can reject it.
Have you checked that there are no Rules operating on your mailbox Inbox? If you've inherited a Blocked Senders Filter rule from the mail platform in use prior to 2018 then Delete it.
Select here: Sign in to TalkTalk Mail
Enter your full lineone email address and the lineone password, select Sign in.
Check the Inbox first and then check Spam and Trash folders for mail messages that may have been diverted from the Inbox. Bear in mind the spam and trash folders normally contain mail not older than 30 days.
Select the New email button, or pencil icon if using a mobile browser, to compose and self-send the same mailbox a mail message. Check that the message sends without error, is copied into the Sent folder and arrives and stays in the Inbox.
Mail not reaching the Inbox could mean there's a Filter rule, including an Auto forward which is a special filter rule, that's diverting, discarding or blocking mail.
- Select the Main settings menu cog icon top right on the blue header
- Select All settings, or if using a mobile browser it's Menu then the cog icon for Settings
- Select Mail and scroll down to Rules
Select the chevron icon > to see all defined Rules
If there's no rule defined, that's perfect
- To delete a Filter rule including any Auto forward
select the X icon to the right of the rule
The icon background will turn red X
- To confirm you really want to delete this Filter rule
Select the blue Delete button
Let us know of any error message, or if mail did not arrive in the Inbox or disappeared from the Inbox. Collecting mail messages with a POP3 mail account or mail collection service, like Gmail, may be deleting messages from the online Inbox.
