On the camera details page, you have some options to tune the storage duration vs the quality of video stored.
As some quick background, the amount of storage a camera can hold is dependent on how much motion a camera sees. A camera that sees very little motion, can store almost 30 days of video under the default settings and a camera that sees constant motion might get as few as 10 days of storage.
As the user, there are some camera settings that will allow you to optimize either for higher quality video or more storage. Go to the camera details page and on the right hand side select "Adjust storage/quality"
With the above settings, you can select what is most appropriate for your organization. Furthermore, if you need more storage than the camera can accommodate, then we also offer cloud archiving where you can store an unlimited amount of video in our cloud.