Has this issue been resolved for Sasha Leyberyuk ?
I have a similar issue having problems authorizing my ArcGIS Pro account that I purchased online.
A slight twist is that I am normally from New Zealand and would easily access my support there. But I am currently in Ghana (completely opposite time zones), I have tried to contact the ESRI reps there but I have had no response.
The thing is that I need this authorization to be working pretty pronto as I am hoping to run some community GIS training early next week (which will potentially gain ESRI some new cutomers). If this can't be done in time I'll have to revert back to QGIS.
I think the problem might be with my ArcGIS Online subscription. I have a public account I have been using.
When asked to activate a subscription it gives you the opportunity to use a current log in (Makes sense not having to have multiple private accounts - after all I am just one person!), so I tried to use this but I receive an error message.
If you are prepared to look into this for me I can send you an email with the screenshots for every step I've taken which has resulted in ArcGIS Pro telling me I am not authorized.