When should I use the "Check health" button next to a proxy or account?
The "Check health" function next to an account is useful when you suspect that your account may have some errors, and it's recommended that you use it before enabling an account.
If you account gets disabled by itself, the "Check health" function may offer you some insight on what happened.
The "Check health" next to a proxy, check if the proxy is online and it can connect to Instagram successfully. It also verified that the proxy is not too slow and doesn't leak any data it shouldn't.