Black Video Recordings

I have two recordings that when I attempt to play them back are just black. All other recordings are fine. I have checked the RSSI for my doorbell is -41. I have tried playing the videos back on wifi, cellular, and on my desktop and they all just play back black.I need to provide these two videos to a vendor that is investigating a delivery that the carrier claims they made but I never received. About 3.5 hours after initiating the trace of the delivery my package magically appeared. The time stamps on the two videos that are just black coincide with the supposed delivery and with when the package was actually delivered.