Ship tree bug

Dear Programmers!

The Empire has seven levels, I can not get past the 8 level, the synergy accomplished, credit is available, I can not buy a boat.
(Windows 10, Intel I5 2400, R9 200,)

thanks to:



Not a bug, new progress system.

Info from patch notes 

You need to buy and develop the previous ship to a certain synergy level
You need to buy a certain number of ships from previous ranks
These requirements do not affect Premium and DLC ships
Premium and DLC ships are accounted for when buying other ships