Woke up robot from winter sleep and wouldn't move

by lisa
(cold spring, NY)

I have had the dolphin diagnostic for 8 seasons without issue. This year we powered it up, hooked up the hose and it just sat there. Would not even go all the way down/ No twirling top part, no moving treads. Any ideas? I do think the blue cord has become loose at the end where it plugs into the power source. I hate to have to buy a new one if it's something fixable