[WP Job Manager] Restrict Number of Categories a Listing Can Use

Hu guys,

I’m using the Listify theme together with the WP Job Manager plugin to create a business directory.

In order for my membership levels to work, I need to restrict the number of business ‘categories’ that new listings can assign themselves to. At the moment, new users/businesses can select multiple business categories by means of clicking a category from a drop-down list, then re-entering the list to select additional categories.

Is there a way of restricting a user to only one category per listing?

Many thanks for your help.