Problem in the import of WSDL to PI

When trying to import a specific WSDL to PI 7.1 show me the following error:

Unable to convert imported document to WSDL

Reason:

Element "simpleType" is not permitted in the "/schema/simpleType("__MANDT")/restriction" elementCheck the selected category

But, the strange is that if I import a other WSDL, it works.

Someone could help me?

Tks,

Erik Brison