The tailgate does not open…Volvo V70, Bj 2008

The rear flap on the V70 (2008) does not open any more. When pressing the handle on the trunk or remote control, one hears a click – but nothing happens. I forged a curved “flat iron” from a threaded rod, so I was able to loosen the panel in the area of the windscreen wiper engine and bend into the drive room. So I can hold down to the lock with one hand – only what should I do now??? Recognize disguised lock, in which a wire rope goes in from the handle, which moves when you press the handle. At the bottom – seen from above left – I feel a thicker wire rope at which I can pull and then I can hear like an opening of the lock, but nothing is happening!??? Can someone give me advice! Have already read several dt. and engl. forums, but at this point I did not get any further… Thank you! Timo