I tried all combination files available in shell but same error
combination file name COMBINATION_FAC_FA60_A520FXXU8ASB1
FLASH INSTRUCTIONS:
1. Choose correct flash file(s).
2. If you have PIT file chosen, then you must check 'Repartition' option.
3. Check flashing options if needed (Repartition, EFS clear, Boot update).
4. Power on the phone in download mode (turn off phone, press vol.down + home + power).
5. Connect the phone to PC with USB cable, install drivers if needed.
6. Press 'Flash' button.
Operation: Flash
Selected model: SM-A520F
Software version: 38.11
File analysis... OK
Total file size: 0x5E567DF4 (1509 Mb)
Searching USB Flash interface... COM6 detected
Setup connection... OK
Set PIT file... OK
Reading PIT from phone... OK
Sending sboot.bin... OK
Sending param.bin... error timeout
Done with Samsung Tool PRO v.38.11