Why are my emails deleting instantly and not remain in trash ?

lynwalcott wrote:

I used to be able to delete my emails manually from the bin on AppleMail on my MacBook, but now if I press delete, they are gone forever ?

Have you quit Mail, shut down and rebooted the Mac to test...

Verify your settings... for each active account

Mail>Settings>Mailbox behavior

ref: Mail User Guide for Mac

lynwalcott wrote:

Thank you I have tried all this

Anything else you already tried...(?)

My only other suggestion short of re-installing the macOS—

for problem accounts you can try to sort things out by deleting all the account(s) from the Mail.app, then add them back.

Remove email accounts in Mail on Mac

Remove email accounts in Mail on Mac - Apple Support

Add email accounts in Mail on Mac - Apple Support

Add email accounts in Mail on Mac - Apple Support

Note—

IMAP accounts stay on the server, so no local loss, when you re-sync

POP accounts download and remove from the server—therefor save your inbox/sent box if you want them

“On My Mac" is just that, local folders you created and moved mail into. So no loss

You can call Customer Support  (800) MY–APPLE (800–692–7753)

or on line  https://getsupport.apple.com/

Outside the USA—Contact Apple for support and service by phone

See a list of Apple phone numbers around the world.

Contact Apple for support and service - Apple Support