RangingListener empty list after multiple calls


I made an Android service who just starts an AsyncTask with the nearest beacon major and minor as parameters. This service is started whenever I press a button and stopped when the AsyncTask is called. Now the thing is that when I press the button for the first time, it works. After some multiple calls of the service the near beacon list gets empty. Every time again the list is empty. Now if I shutdown my Bluetooth, wait 5 sec and start it again, the list is filled again. Is this a known issue? Is it phone related or app related? Any fixes?

Thanks in advance.