This is a bug of my tool. Why it is not corrected? Well, there is no real use because DB2020 CID49 phones cannot be patched for free and I'm too lazy :D .

The answer: download XS++ v3.1, and connect your phone to it. When XS++ ask you if you want to upgrade the EROM CID to 52, press the Yes button. Download a K610 RED52 firmware, and follow the unlocking guide.