FaceTime Crashing

I have been using FaceTime a lot since March. It worked completely fine on my Mac for several months. Recently, I have been starting to have issues. Sometimes, people are telling me it's not ringing when I call. Even more annoying, FaceTime sometimes crashes when I pick up a call. This seems to happen after I have been using FaceTime for a while. It's like it just stops working. I get an error report that I can choose to send to Apple. It is only an issue on the laptop. I never have any of these problems when I use my phone. My laptop is a Macbook Air from early 2014. I checked for updates, and it is telling me none are available. It shows OS X Yosemite 10.10.5. I don't know much about computers, so I'm wondering if a new laptop would fix this issue or if there's something I can do to fix the problem on this computer.