1,Please reboot of the server to have a try. If possible, we can also try a site reset and see if it repairs the provider. A similar thread for your reference:
SMS_REST_PROVIDER Component Status Critical
2,This issue may happen when IIS default site (used by SCCM) has no SSL certificate bound to port 443. Please try below actions:
Go to IIS and select the top level which represents your hostname. On the panel, click under "Server Certificates" and you should see a certificate with the following name: "SMS Role SSL Certificate".
Then, go Sites > Default Web Site > Right ribbon > Bindings > Select https > Edit > SSL certificate, then choose SMS Role SSL Certificate in the drop down list. Confirm the binding by clicking OK.
Thanks for your time. Have a nice day!
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