If a game has started how can it be deleted as i want to surrender but they won't accept - its been 7+ days

It can't be.

You can surrender, you can vote to end game, or you can be booted.

Or you can be eliminated, gift them all your territories, turn them into blockades or abandons.

Could be a match with a map on development, and when you make changes on map, the game auto-delete himself.