Thank you for elaborating and providing screenshots.
There are few different reasons why the skin is not applied. The two most common are:
1. the EnableEmbeddedSkin
property is set to false
no custom skin is referenced in the Skin property.
2. The Skin property is set to an empty string (Skin="") which is not recommended.
Please verify if this is not the case and let us know how it goes.
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