Missions are missing in Load Game section

Hello. I need immediate assistance. 
I bought the command&conquer bundle from Steam, but I was interested in one game in particular, that being Renegade Command and Conquer. When I installed it locally on my pc, I saw that it didn’t have all the missions it used to have, in the Load Game section. 
I bought the game when it launched, back in 2002, and it was complete, having all 12 missions, but now, the steam version only has 3.

 I looked this matter up on the internet, but no one seems to have gone through this problem as I found no solution to this problem. Can somebody help me, please? Am I doing something wrong?

The only missions that I have access to are All brains, no brawn; Commando training; and Rescue and Retribution. 

Please help me find a solution! Thanks in advance!