There is at least one transaction for which the user has chosen a logically wrong taxkey. This means that the user has created an AP transaction and chosen a taxkey for sales taxes, or that he has created an AR transaction and chosen a taxkey for input taxes.
Lx-Office can fix these problems automatically. For AP transactions it will replace the sales taxkeys with input taxkeys with the same tax rate. For AR transactions it will replace the input taxkeys with sales taxkeys with the same tax rate.