Not accessing my hard drive

On my tablo app says no storage connected
When tap watch on my recordings it says play back error-a mounted desk is required for this operation but is not present
Have many recordings on but plenty storage so hard drive is no full
Has been working fine the past year until now
What can I try

Maybe try this. Turn off TABLO and hard drive and move cable to second USB port. Then turn back on TABLO and hard drive and hope for the best.