URGENT - Fix error with Google Maps API in WP Store Locator Plug-In - Must be able to do this job immedietely

We are using WP Store Locator Plug-in on our website www.yayfoods.com.au/store-locator/
A few days ago we moved our website hosting to a new company/server. Since then we have a problem on the store locator page on our website that I can't fix. I've attached a screen shot of the error message at the top of the settings page on the store locator in WP.
This is the error message returned by Google Maps API in the Browser Console
"Google Maps JavaScript API error: RefererNotAllowedMapError
https://developers.google.com/maps/documentation/javascript/error-messages#referer-not-allowed-map-error
Your site URL to be authorized: https://yayfoods.com.au/store-locator/
_.Re @ js?language=en&region=au&key=AIzaSyClDKQsqJ1xPBw3MFAjEDGfViETS2QJkvQ&libraries=places&v=quarterly:86
xoo-wsc-main.js?ver=2.1:183 updated"
I know this is a very simple thing to fix but I am not a technical person and can't contact my web guy.
Please only respond if you are free to do this job straight away. I have to have this fixed in the next 2 hours.