Issues with custom bed

[modella]

Hi everyone! I'm getting into making objects, but I'm having a little issue, specifically with the bed I'm making. The middle is sinking in ;___;

 

 

I'm assuming it may be a weight issue, but I did my best in terms of transferring the weights from a game bed to this custom one. But here is the package file if anyone may know how to help

 

modellanewbed.package