You may find the following error messages there:

Object
5113:Array[1]
0:Object
code:"100008 - INVALID_VALUE"
title:"Brand not available"
path:"/products"
jsonPath:"$.productVariations[?(@.sku==\"5113\")].productDescription.brand"

Check your mapping of the affected catalogue under Brand and consult with Otto Market which brand can be used instead or whether the brand needs to be reactivated afterwards.

Attention! If you use more than one brand, you cannot use Custom Values. Instead, use properties, for example.