New board, used about 3 times working on a sketch, working on the door sensor sketch with Telegram. After a few times debugging the sketch it just stopped working and gave me the above error. I tried to load a blank sketch to make sure it wasn’t something with the sketch but to no avail. I have seen that in other posting people have had this same issue with the development board and soldered a 10 uf cap to the en pin. This board does not have it and wasn’t sure if it was the same  solution for it.

I did some research on that board and did find the location for EN on the chip, I used the bread board to try the 10 uf cap + side to chip and and to ground, didn’t work.
I have also read that there is an issue with the cheap knock off boards where you have to remove the shield and replace the processor .This board is a Doiting ESP12-F board , so it is a branded board and assume it’s not a cheap Chinese knock off . Thanks

     After many hours of reading and searching, trying several things, I discovered that it was the programming cable that was the culprit. Replaced the cable and now I can access the ESP – 12F , luckily enough I didn’t do more damage than good .

Great!
Many times the cable is the culprit. It also happened to me before.
I’ll mark this issue as resolved. If you need further help, you just need to open a new question in our forum.
Regards,
Sara