Hi I have been using outlook for years.
I have three email addresses. Two gmail and one icloud.

The default which is gmail is not showing up in Outlook. If I do a test then the reply appears on Google mail and on my iphone but not in outlook.

If I do the same with my other address it appears in outlook. I have not configured this to appear on my iphone but is appears in outlook.

This has happened since I replaced my broad band supplier from residential BT to Business BT.
I am still using the same router. it is a fibre optic exchange. I had not altered the passwords.
I am sure this is pig simple but cant see any odd setting.

Would love to have a solution

Mark