I can't repair my jaf it give error -24 -21

hello, i try repairing my jaf box, did all connection right but when i try to write .hex, it give me this error { device missing or unknown device -24} when i click ignore it will continue but when i try to write .bin file it begin to write till it finish when verifying it stop at 80% and give error {write error -21} i don't know what's wrong, plss help. Thanks

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