If you have not enabled 2 Step Verification for your RealVNC account, then you will receive an email asking you to verify the sign-in attempt. Sometimes, however, the location given may be incorrect. The location given in these emails is provided by a GeoIP database which may not be 100% accurate.
This can be prevented by enabling two factor authentication on your account. See Why am I being asked to check my email each time I sign in to my RealVNC for more information.
What should I do?
If your location, public IP address and time of sign in is correct then nothing! Everything is fine and you can approve the sign in. You can use a site such as https://www.whatsmyip.org/ to verify your current public IP address.
If your location is incorrect but the time of sign in and public IP address match what you are expecting then it is likely a mistake made by the GeoIP database we use, or the IP address provided by your ISP.
However if the public IP address, time of sign in and location are wrong and it was not you trying to access your account we recommend you follow the steps in this article: What if my account has been hacked/compromised?