Hi Adrian,
Check your settings. Under Search, Search Address Nearest, current map or Wordlwode.
Radius behavior, do you have it set to Alwsys use, only use after search or do not use?
Do you have a Discrete search filter besides append, A drop down search by City for instance?
A screen shot of your plugin environment and some of the settings on your back end would be helpful.
Here is some more info on your Functionality to limit results (Such as what is your initial search radius. make it smaller perhaps, number to show initially, do you want to disable the initial directory or show all results at start up ) Are you adding the instructions under results label to enter an address or city for best results etc.
Is your map using a google domain to search from, etc etc.
There are a lot of variables and you may need to go back and read either from the settings in the User Interface in the back end, each line has info tab and links to the docs site.
https://docs.storelocatorplus.com/blog/results-order-by-display/
https://docs.storelocatorplus.com/blog/radius-behavior/
https://docs.storelocatorplus.com/blog/adding-radius-selection-first-entry/
https://docs.storelocatorplus.com/blog/no-results-found-label/
https://docs.storelocatorplus.com/blog/search-panel-settings/
https://docs.storelocatorplus.com/blog/location-search-enhancements/
, radius search