most of spd cpu android shows this error in volcano . please read the phone partion
in this condition u need to wite pac file firmware by research download tool
How To Read Flash SPD Android pac file?
1.Mobile On Condition.
2.USB Debug Mode Enabled.
3.Minimum 2Gb Memory Card Inserted into Phone With 32 BIT Formatte.
4.Now Connect To Pc Port.
5.Open Volcano Box Software.
6.Go to SPD Tab.
7.Select 6820/8810.
8.Select One-Key Root.
9.Select Backup Flash from Option.
10. Untick Auto-Detect Pinouts.
11.Click on Run.
12.Mobile will Detect Phone on ADB.
13. Some Times After Volcano Box Software Ask Where Save File.
14.Make Flash File Path.
15.Some Times After Mobile Read Done
now u can write this file by offical tool like research download
tool download link.