This happens a lot with our oven. We have a great, easy water based cleaning cycle on it, but our housekeeper crews don’t really know how it works. So, often I am the deep cleaner when I visit. I make a paste mixture baking soda, with water and vinegar. I leave it on a couple of hours minimum. Then take vinegar that you can put in a bottle to spray on, or pour in the bottom. Let
it foam up. I also understand lemon can be used, but I never seem to have a lemon to try. My baking soda and vinegar method has had to be used a couple times to get things really bad to start coming up. Then I run the normal cleaning cycle. I also hear you can use dryer sheets to scrub the racks, which I plan to try soon. Magic erasers also can work well, especially on cooktops and on the oven door glass splatter.
...If you have any tips to get deep dings out of a stainless fridge - let me know. The YouTube tricks to freeze with canned air to pop out, and suction cups, haven’t worked for me at all.
Best of luck keeping on top of it all!