Hi Sandyt,
The bad news is there is no adjustment.
The good news is drop-down oven doors eventually loose their 'spring' and there is a brisk aftermarket turnover of these items.
I suggest you log on to 'http://ukwhitegoods.co.uk'.
Scroll down and click on the cooker and oven symbol.
Now click on the Diplomat logo.
In the fourth line you will see 'oven door hinges'- click it.
If you can't find a match for your cooker or you are in any doubt about the match you can email them by using the Contact button at the top of the page.
Cledlyn
August 2008