I bought a used Yaesu VX-6E, in good condition. Waterproof, shockproof, lightweight and I found the accessories I need available for this model. I fly a paraglider and use these radios for that. I bought a hands-free kit, PTT mic and headphones. 20, not Yaesu, they don't make one but it seemed well made. I'd been using the Baofeng radios before but they kept failing in various ways and this radio and hands-free kit felt far more robust.
But when I plugged the Handsfree kit in it did not work. The headphones worked but the PTT did nothing, a transmit bar flashed for a split second and then nothing, no mic, no PTT. I spent hours poring over the manual trying different things but nothing made any difference. I asked the vendor of the hands-free kit but they didn't know why it was not working, the kit is specifically for the VX-6, Vx-7.
So I bought another one from a different seller. This one was exactly the same. headphones but no PTT or mic. So I thought it must be the radio. So I bought another VX-6E, brand new this time. It arrived today and I tested it and the same, the headphones are good but no PTT or mic. After looking closely I've also realised that the only handsfree kit for this radio is this one. There are lots of places selling it but they're all the same so buying a third one seems crazy.

I bought a Yaesu FT-4V first but had to sell that after weeks of buying kits that didn't work. I've a box full of useless radio bits now and really don't want to go back to the Baofeng radios but I'm running out of options if I cant get this one to work.

I'm at a complete loss. If anyone knows the VX-6E or has any advice about something I may be missing?