3776553 - Fail to insert seamless planning model when using additional domain in SAC excel add-in

• In the SAC Excel add-in, inserting a Seamless Planning model fails when signed in via the additional hcs.cloud.sap domain.
• Error message:
  "An error occurred while inserting [model name]."
  "Error [Application]: (#81) Server metadata was not a structure json."
• Accessing the Seamless Planning model in a browser via additional domain hcs.cloud.sap works, while the additional domain required adjustments in Trusted Origins for SAC web has been done as per 3774301 - Seamless Planning Model fails to load via hcs.cloud.sap Domain in SAP Analytics Cloud (SAC).

SAP Analytics Cloud, add-in for Microsoft Office

sac excel add-in, seamless planning, hcs.cloud.sap, additional domain, server metadata was not a structure json, error 81, application 81, model insertion error, datasphere, tenant link, trusted origins, analytics.cloud.sap, wave 2026.15, excel addin login domain , KBA , LOD-ANA-OF-XLA , SAP Analytics Cloud, add-in for Microsoft Office , Problem