I used tape on mine, but they're a little different style. Like the other poster said, it sounds like your cord is shot. Can you go back to the manufacturer on this, or was it a DIY deal?
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I think at this point you might need a new cable, since the connection socket most likely loose on the inside. Once you got a new one, try ziptying the ends below the connection joint (to ease the stress on the joint), ziptie it to the frame (as you did last time) and bonding the connection itself with epoxy resin (could be found in hardware stores).
While using adhesives (epoxy), make sure you cleaned the surfaces very well
An alternative to ziptying to the frame or using epoxy would be to try ziptying the ends together. One slightly loose zip tie on each cable end (just below the base of the connector). Then using one or more zip ties, tie the two ends together. At least the ends won't disconnect this way, but whether or not the connection is good enough is a different story.
Could be a good temporary fix until a new cable is purchased.
Inside the cable there are 8 or so smaller wires and when I looked up the cable I couldn't find the same one anywhere
Can you post a photo of your actual connector? Inspect it closely for broken/damaged pins. Where do the other ends of these cables go? If it's a proprietary connector that's hard-wired into the motor, then replacement cables might not be readily available. If the connector is broken and replacements are not available, then I would probably consider replacing the connectors with a soldered connection.
Adhesive lined heat shrink tubing will likely do what you need. If not, a locking connector such as an ampseal or sumitomo or deutsch(?) connector.