No RetriveEntityRequest since custom Cumstomer Field on Entity

Hello,

We have created a new custom customer field in CRM 2016 SP1.

Since this we don't can execute a RetiveEntityRequest

RetrieveEntityRequest a = new RetrieveEntityRequest();
a.EntityFilters = EntityFilters.Attributes;
a.RetrieveAsIfPublished = true;
a.LogicalName = "new_mitgliedschaft";
RetrieveEntityResponse b = null;

b = (RetrieveEntityResponse)crmOrgService.Execute(a);

The Last Line will Fault: OrganizationServiceFault: Found an integer attribute with unrecognized format: new_kundeidtype

I use the last SDK version.

The incident is existing on both: CRM OnPremise and CRM Online

When I delete the custom customer field on the entity the RetrieveEntityRequest will work.