Yield curve &1 in &2 has ref. interest rates with the same maturity date

What causes this issue?

The yield curve &V1& in currency &V2& for &V3& contains reference
interest rates with the same maturity date.
Either the yield curve contains incorrect reference interest rate grid
points, or the maturities specified for the reference interest rates 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 yield curve or the incorrect
maturities of the reference interest rates.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.