The DVR-4480 is pre-installed with a microSD card. Since microSD capacity is low, there are restrictions on recording modes and bitrates. Therefore, this model does not have a continuous or normal record schedule option.
However, connecting a USB hard drive or installing a hard drive of at least 512GB capacity up to 4TB enables higher performance options as per a normal DVR.
Check the article How to Set Up 24-hour continuous recording for a Camera to know how to get Normal or continuous recording.
NOTE: If the larger storage is removed, all scheduling and settings that were set for that storage will revert to settings appropriate for the smaller Micro SD storage.