enhancement: Fixed the problem of reconnecting to instances of long heartbeat connections

[robotLJW]

What type of PR is this? /fix

What this PR does / why we need it: fixed the problem of reconnecting to instances of long heartbeat connections

Which issue(s) this PR fixes: Fixes #983

Special notes for your reviewer: @tianxiaoliang @little-cui

Use case description:

There is no need to add a new use case. Previously, the related function use case has been included.

Does this PR introduce a user-facing change?

No

Additional documentation e.g., usage docs, etc.:

No

Verify

1. Register an instance, use a long connection to send a heartbeat, and then delete

2. try to re-register