Basis spread curve &1 in &2 has basis spread IDs with the same maturity

What causes this issue?

The basis spread curve &V1& in currency/tenor pair &V2& for &V3&
contains basis spread IDs with the same maturity date.
Either the basis spread curve contains incorrect basis spread ID grid
points, or the maturities specified for the basis spread IDs are
incorrect.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Correct the incorrect grid points of the basis spread curve or the
incorrect maturities of the basis spread IDs.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.