This is usually a corrupted database or missing fighter pictures.
If you want a fast, deep, and completely offline sim that runs on a potato PC, the WMMA3.zip file is the perfect choice. WMMA5 is better, but it requires more processing power and a learning curve. DOWNLOAD FILE - World of Mixed Martial Arts 3.zip
When you open the game for the first time, it will ask for a license key if you have the paid version. If you are using a free trial .zip , you will be limited to 1 year of in-game time. This is usually a corrupted database or missing