A:Answer Thank you for reaching out to us! Kindly be informed that the issue can be caused by a battery problems in the handsets. Also, please check to see if you have a call limit with your phone company. If you need further guidance, kindly let us know and we will happily assist you. You can contact Support Team via Live Chat on the Panasonic Website, Contact Us option, Mon-Fri, 9am-5pm EST.