Welcome to the community. 
First of all, if your copy of the game is cracked or pirated, then that’s the cause of the issue you’re experiencing. The trainers are only made and tested for the store-bought versions.
Otherwise, the most common cause of trainers not injecting correctly into games is due to interference from security programs on your PC or network. Amongst other things. Note that simply adding WeMod to the antivirus’ exceptions after it has already blocked the trainer won’t undelete any critical WeMod files that the antivirus has deleted.
See this post for full instructions and give them all a go, from top to bottom: "Wemod failed loading the cheats into your game" / "We’re having trouble downloading the cheats" - #2 by Ravenfyre.