Can you repair bad ESN

[tedshark]

I have an HTC DNA phone that has a blacklisted IMEI, I did see someone that tried and was not able to do it, he said it could be done with an octopus box, I am not finding much information related to this, so I'm asking the question here.
Can you repair this phone or refer me to someone that can.

[rich hathaway]

HTC is a pita to work on, i can do them but not cheap.