ok so If I understood you. I went into my platformio.ino and change env_default from melzi_optiboot to just Melzi and ran upload melzi and the I got this
Linking .pioenvs\melzi\firmware.elf
Checking size .pioenvs\melzi\firmware.elf
Building .pioenvs\melzi\firmware.hex
Memory Usage -> http://bit.ly/pio-memory-usage
DATA: [== ] 15.3% (used 2513 bytes from 16384 bytes)
PROGRAM: [==== ] 41.6% (used 54112 bytes from 130048 bytes)
Configuring upload protocol…
AVAILABLE: arduino
CURRENT: upload_protocol = arduino
Looking for upload port…
Auto-detected: COM3
Uploading .pioenvs\melzi\firmware.hex
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.00s
avrdude: Device signature = 0x1e9705 (probably m1284p)
avrdude: reading input file “.pioenvs\melzi\firmware.hex”
avrdude: writing flash (54112 bytes):
Writing | avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding