If you have tried the steps as witten before:
You can try to recover this by yourself with the bootloader v1 (Not v2!) as described here: forum.heinrichsweikamp.com/read.php?2,4071
See "If you have firmware <1.90:" and following.
and did not succeed, please try again or contact us. In almost 100% of such issues we do exactly what is written in the link above (With the v1 Bootloader, not v2!) and can recover the units here quickly.