I use this Prada Saffiano for years, and the handle is impossible to restore by leather care product.

I entrust an expert to help me.

I tried using crack filler to fix, however the effect is a disaster.

Some areas faded, and the while colour of leather substrate showed.
Restoration
Handle
My intention is to fix, but the expert told me the only solution is to replace it.
What is the first step to replace the handle? The answer is to find or make the leather with exactly same colour and texture.

It is amazing that she has the leather!
The second step is to remove the existing handle and destruct it.

There is white “bone” inside.

Use the new leather to wrap the “bone”, stitch the edge, then attach to the buckle on the body, stitch, at last edge finishing.
When I look at the handle, I really cannot tell it is not the original one!
Coloration

The colour is so homogenous and the luster is impeccable, too amazing!
Piping

The piping is still in good condition, and I feel this can be easily tackled with Famacolor. I didn’t expect her to manage it.

She applied dye to the whole bag, which made the piping also good.
Summary
The whole restoration cost 800 RMB, but with the final outcome and I can use the bag for another 8 years for sure, I am more than happy to pay.
Your writing is always so clear and helpful—thank you.