Thank you!
Do you have some pictures to show?
It is commonly done with degreasing using Degreaser-2.2.
This product will emulsified the grease and you will see milky-like color that is towel extracted and rinse off with Rinse-3.0.
In most situations, the topcoat is damaged and will need a refinishing.
The dyes may be faded or bleed off and may be rejuvenated by hydrating to bring it to the surface (just like bring out tea color with hot water).
Another very necessary restoration is to replenish the Fatliquor originally there that affects the leather softness.
Meanwhile waiting for your pictures to give you a better assessment, and how best to restore it.
Roger Koh
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