Thanks for your message. Honestly, we don’t think that’s the real cause of the issue, because even if the company name was an empty string, this would not get saved as null value in the database, and so for this reason there can’t be any crashes due to PHP Fatal Errors.
Our suggestion in these cases is to enable the debug mode on your WordPress website to make sure to read the full server error message whenever you get a crashed page. Also, testing the booking process with an incognito/private session of your browser may be helpful to debug certain behaviours.
Lastly, the company name gets the default value of the plugin name (VikRentCar) upon the installation, and so this value is always changed by all our clients. It should never lead to server errors. Turning on the debug mode or using a private session with your browser should help you understand where the issue comes from.