How to active vxdiag Benz Xentry EPC WIS by yourself?

Mercedes Benz C6 with Xentry V2019.12 got error "No access authorization code! Please contact the User Help Desk". The solution is to open the "Xentry License" to active Xentry.

http://blog.obdexpress.co.uk/2020/02/26/how-to-active-vxdiag-benz-xentry-epc-wis/