What is the actual output of display ssh server status CLI Command?
Generally if SSH is already enabled you should only disable SSHv1 in favour of accepting connections from SSH Client based on SSHv2 only.
On Comware if SSH Version display the value 1.99 it means that SSHv2 is preferred but a fallback to SSHv1 is permitted during negotiation with SSH Client not ready to negotiate using SSHv2, if instead SSH Version displays 2.0 it means that only SSHv2 is accepted.
To disable SSHv1 go with undo ssh server compatible-ssh1x CLI Command in System-View mode and verify with display ssh server status again (or, alternatively, using a telnet on 127.0.0.1 port 22: telnet 127.0.0.1 22 to see the output reporting the actual SSH version the SSH Server is using).
More here and here (not specifically about HPE 5510 but related to SSHv2 on Comware).