Failure to boot after power failure

I have an issue with a Fortigate 80D.  After a power failure the unit is inaccessible via IP.  When I console into it, it has a message regarding a power failure and I have to press f1 to continue or f10 or something for another option.  Sorry I  don't have the exact verbiage.  After I press f1 the system loads properly and the unit is functional once again.  So it seems after every power failure I will have to console into the unit and press f1 in order for it to come back up.  Of course I've told the customer to invest in a UPS.  Is there a way to have the unit load normally after a power failure?  This does not seem right.  I have loaded the most up to date firmware as well.

Thank you for any assistance.