Research stuck at -5?

I was researching for 3D version 1 but then the research number got stuck at -5. I can’t do anything except train myself and the employees and look at my game history.

Is there a solution for this or do I have to restart the whole thing again?

we would like to investigate this further, can you please get in contact with us at support@greenheartgames.com

Thanks.

If I remember clearly, doesn’t 3D -6 and -7 can be research from the RnD department in the last office?