If you have phone numbers in your Bing ads you will find them disapproved in June 2015. Instead of phone numbers in ads you can use Call Extensions for Bing. Call extensions are useful because they can show both your website and phone or just a phone number only. If you have a local business with no website, this is the best way to do call only Bing Ads.
What happens when I use both Call and Location Extensions?
"Call Extensions can be used together with Location Extensions. When these two features are used at the same time, the phone number displayed (coming from one or the other extension) and the availability of click-to-call depend on the device where the ad is being viewed. The table below describes what you can expect." - Bing Ads