Windows suddenly thinks I am in Indonesia rather than in Punjab, India

Because Windows, Google Maps, and Find My Device all show the same wrong country, this is unlikely to be caused by the Windows time-zone setting alone. Windows location can use nearby Wi-Fi access points, IP address, GPS, and other radio signals, so an incorrect Wi-Fi geolocation record can affect several services even when the public IP looks correct. As a temporary safeguard, set the time zone manually to India Standard Time so scheduled tasks and timestamps remain correct. Then confirm Location services is enabled, set Punjab as the Windows default location, and test once on a different Wi-Fi network and once with Wi-Fi disabled if possible. Do not reset or reinstall Windows; neither action corrects a third-party wireless-location database. Record the affected Wi-Fi network, approximate time, screenshots, and results from both services. If the issue continues across networks, submit the evidence through Microsoft support and the mapping-service feedback channels

Nothing really worked for me, my Ip is showing my location as Ludhiana, Punjab but google maps is showing me in Hanoi, Jakarta

The "Country or region" setting in Windows controls the local content and services you see, like in the Microsoft Store .