When I delete pants from my male sims they become nude how can I fix this issue?

Hello, Everyone 

I was wondering if anyone knows how to fix this issue, so everytime I make a male sim when I remove their pants they have no briefs or boxers on. Does anyone know why this is happening and how to fix it? It also happens when I am choosing swimming trunks for my male sims too.

I would really appreciate it if someone can help me out. 

From 

Poppdreamer