AdWords offers 
several different strategies for configuring filters for your Google My Business locations. However, users sometimes choose filters that do not match any locations, which results in no location extensions appearing with ads.
What's changing?
Starting on 
February 14, 2017, AdWords will perform a daily check to determine if the following 
location extension feed item filters are not matching any Google My Business locations:
  
If any such invalid filters are found, they will be automatically cleared as outlined in the updated 
Location Extensions guide.
Please keep the following details in mind:
  - The periodic check will only clear matchingFunctionfilters on aCampaignFeedorAdGroupFeedfor location extensions (placeholderType = 7). It will not clear filters on those objects for location targeting (criterionType = 77).
- The periodic check will not clear matching functions of the form IDENTITY(false), since these indicate that you want to disable location extensions for a campaign or ad group.
What you should do
  - To minimize the impact of the periodic check, regularly review your application's location feed setup and ensure that you are choosing filtering options on your PlacesLocationFeedData and matching functions that actually match locations in your Google My Business account.
- Make sure that your application will be able to handle the filter changes made by the periodic check.
If you have any questions, please post on the 
AdWords API Forum.
 - Josh Radcliff, AdWords API Team
 - Josh Radcliff, AdWords API Team