According to your picture...
You have a genuine electric hose which is designed to fit together with the sidekick and make the electrical connection automatically. I think the hose handle may not be fully inserted as I mentioned above.
I will add that my Mother had a problem with getting the sidekick all the way on the hose handle, turns out the hose handle’s metal end was out of round...someone (a previous owner of the vacuum) had crushed it somehow a bit and tried to make it round again with pliers and it was very difficult to get the sidekick all the way on and off...(we think this is why they got rid of the entire vacuum) I had to work on it for an hour or two with a vice to improve it but it was never perfect and still difficult to get it on and off though I could do it with some force but with Mom having arthritis in her hands it was still too hard for her so I got a new hose handle from Aerus and it works beautifully with no problem for her. If this is your issue, you may need to purchase a replacement hose handle...since it genuine, you can get it from Aerus. And if you want to change it yourself there is a special procedure to avoid breaking the electrical conduit piece underneath so ask them for those instructions on disassembly and reassembly, or they can do it for you. I don’t recommend buying a used one because they too, could be damaged and out of round and that wouldn’t help. If this was the issue, be careful not to damage the replacements metal end, avoid stepping on it, dropping it on the ground, etc.
Jon