X-Appengine-Country header shows wrong country - google-cloud-platform

Question

<dependency>
<groupId>com.google.cloud.functions</groupId>
<artifactId>functions-framework-api</artifactId>
<version>1.0.2</version>
<scope>provided</scope>
</dependency>
POM dependency given above
import java.time.Instant;
import java.time.ZoneId;
import com.google.cloud.functions.HttpFunction;
import com.google.cloud.functions.HttpRequest;
import com.google.cloud.functions.HttpResponse;
public abstract class CommonGCF implements HttpFunction {
private static final String name = CommonGCF.class.getName();
protected String m_Client_IP = null;
protected String m_Client_Country = null;
protected String m_Client_Region = null;
protected String m_Client_City = null;
protected Instant m_api_invocationTime_UTC = null;
protected ZoneId m_Client_ZoneId = null;
/**
*
*/
public CommonGCF() {
}
#Override
public void service(HttpRequest request, HttpResponse response) throws Exception {
m_api_invocationTime_UTC = Instant.now();
m_Client_IP = request.getFirstHeader("X-Forwarded-For").get();
m_Client_Country = request.getFirstHeader("X-Appengine-Country").get();
m_Client_Region = request.getFirstHeader("X-Appengine-Region").get();
m_Client_City = request.getFirstHeader("X-Appengine-City").get();
m_Client_ZoneId = this.getZoneId(m_Client_Country);
}
protected ZoneId getZoneId(String m_Client_Country2) {
System.out.println("received m_Client_Country=" + m_Client_Country2);
if (m_Client_Country2.equalsIgnoreCase("IN")) {
System.out.println("returning Asia/Kolkata");
return ZoneId.of("Asia/Kolkata");
}
System.out.println("returning UTC");
return ZoneId.of("UTC");
}
}
m_Client_Country = request.getFirstHeader("X-Appengine-Country").get();
returns TW when i invoke my cloud function from India.
when i check for my ip using other services it is showing correctly as India.
No VPN used. It was working until yesterday.
log from Google log console
2020-09-23 16:17:15.143 IST RegisterGetProfile am11zdsz2weq received
m_Client_Country2=TW
Any guidance?