Step 1: Go to Gmail on Chromebook or PC.
Step 2: Click the Show Search Options icon thst is depicted below.
Step 3: Type the email or domain name (@.......) into the From dialog box. The email or domain name would be on the emails that is being blocked and sent to spam.
Step 4: Then click Create filter.
Step 6: Check the Never send it to Spam box
Step 7: Check the Categorize as: box and change it to Primary
Step 8: Click Create filter.
Note: filter will not be applied to old conversations in Spam or Trash