Lsass.exe high CPU usage on Windows Server 2012 R2 for HTTPS request

Recently we faced CPY spikes on our production servers & our web applications runs on Windows Server 2016 as well 2012 server. It looks as follows:

IIS with 10 applications running with SSL: MVC website (.Net Framework 4.7.2) & Webservices MS SQL Express 2016. If the traffic increases, the CPU for lsass.exe increases.

I have tried the following but no luck still,

1. Changed RSA byte array size to 2048 from 4096
2. Enable only "PKCS - Key Exchanges" using IISCrypto → Best Practices
3. Updated the latest windows update on the system
4. It is workgroup system not DC [Domain controlled]
5. DNS properly configured

Any help appreciated.