The remote SSH server is configured to allow key exchange algorithms that are considered weak. This is based on the IETF draft document Key Exchange (KEX) Method Updates and Recommendations for Secure Shell (SSH) RFC9142. Section 4 lists guidance on key exchange algorithms that should not and must not be enabled. (Source: Tenable Nessus)
As this issue is assessed as low severity, users may evaluate their environments and decide if updating is required.