tried and tried... i was sure that my esp died.. I tried windows version of these flashing tools, after tons of trials i succeeded to upload it.
Check the cables, change the cables, change the tool.. probably u'll succeed too.. (Try both 0 low, 2 high or all variations i recommend the standart tool for windows, i guess it was cm.....smthing smting, that has a connection test on it, it'll tell you the true combination of firmware mode:)
Btw after succesfully burning the new firmware i used the pytool as usual without any problems..