Error message when changing Topic name on Opportunity

Hi,

When I want to change a topic name I get an unexpected error, never seen this before.

Any idea?

Unhandled exception:

Exception type: System.ServiceModel.FaultException`1[Microsoft.Xrm.Sdk.OrganizationServiceFault]

Message: Validation error: Stage ID is not valid for Business Process.Detail:

<OrganizationServiceFault xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.microsoft.com/xrm/2011/Contracts">

  <ActivityId>55d068ff-54f0-41ef-91be-32ceb7c35aaa</ActivityId>

  <ErrorCode>-2147220970</ErrorCode>

  <ErrorDetails xmlns:d2p1="http://schemas.datacontract.org/2004/07/System.Collections.Generic" />

  <Message>Validation error: Stage ID is not valid for Business Process.</Message>

  <Timestamp>2019-05-27T09:03:47.6877438Z</Timestamp>

  <ExceptionRetriable>false</ExceptionRetriable>

  <ExceptionSource i:nil="true" />

  <InnerFault i:nil="true" />

  <OriginalException i:nil="true" />

  <TraceText i:nil="true" />

</OrganizationServiceFault>