You have what is known as dye transfer, colour has redyed the leather. The usual process for removing dye transfer is to use LTT Maxi Cleaner (a cleaner specifically designed for the job - it is different to a normal leather cleaner) and if this does not work to call a technician who will have much stronger products to remove it. It depends how far it has penetrated the finish on the leather how easy it is to remove.
The use of a good leather protector (one that works- many don't) will help inhibit this type of thing happening again, as it will be easier to clean off.
It is not a good idea to try anything else without taking expert advice as sometimes the products you use can contain silicones which may make refinishing impossible, new finish will not adhere to silicones.
Please do not try nail varnish remover, acetones or alcohols as these may make the matter much worse.
A word of caution to all those who post on here with all these household products to try - they do not work and in many cases it will make matters much worse.
Leather care consultants to the furniture and cleaning industries
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