Automatic Shutdown after 15 minutes on battery

Sounds like an aged battery that's rapidly dying.  Run a powercfg /batteryreport at a command prompt with admin privilege.  What is the current charge capacity of the battery?

@ejn63

Attached the screenshot for your reference
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The battery has lost about 30% of its design capacity.  Before the shutdowns started, how long was the system running on battery (on average)?

If that 30% is one bad cell, the voltage may be dropping enough to cut off the power.  Does the system run normally on AC power and is the AC power adapter recognized?

@ejn63​ the system was running approximately for 2 hours on battery.

yes, the system runs normally on the AC power.

Check your power management settings -- is the system set to shut down when idle?

@ejn63​ no the system is not set to shutdown when idle

Unless there are other issues, such as intermittent failure to recognize the AC adapter, it sounds like a new battery is the way to proceed.