Gmail offers two ways to block unwanted email from specific senders: a filter and the Google Block option in the email itself. To unblock an email address from a filter in Gmail, remove that email address from the filter you created to set up the block. If the filter contains multiple email addresses and you want to continue blocking other email addresses or domains in the filter, edit the filter to remove only the email addresses you want to unblock and keep the others to continue blocking. After the filter is updated, new emails from addresses removed from the filter will appear in your Inbox.

Gmail removes an email address or domain from your blocked addresses list through the Filters & Blocked Addresses page in settings. The first step is to find the filter that removes emails.

Select Settings (the gear icon), then choose Show all settings.

Go to the Filters and Blocked Addresses tab.