Take the time to steam the oven once a week with water and some detergent.
In this case, you will not have to resort to global cleansing.
Mix 1/2 cup liquid dish soap with 1/2 cup baking soda and 1/4 cup white vinegar.
Mix everything together and apply it all over the oven using an old toothbrush or abrasive sponge.
Now let the solution soak in, wait overnight and the next day wipe with a sponge and clean water.
Place a container on a baking sheet with 20 g of powdered citric acid added to 200 ml of water.
Close the oven, wait until the water boils and condensation appears on the door.
Important condition: after turning off, wait until the oven has cooled down almost completely.
Afterwards, wipe the surface with a sponge, removing fumes and dirt.
Treat the inside surface of the oven first with table vinegar, then apply baking soda with a damp sponge.
Leave the oven like this for a couple of hours, and then wash with warm water.
If the stains persist somewhere, rub them with a sponge soaked in vinegar.