Memory capping problem 16gb capping at 8gb

Not sure if this is the correct place to post this, first time using the site but I need some help.

I am currently running a 16gb setup on my pc running windows10 and have a big problem. Every time I use applications that are memory heavy I run into an error making me close down the application or memory/file corruption or leakage may occur. However, if I check my task manager I can see that the memory usage is at 80% and only using around 8gb or less(I have actually added up the amount of space every single app have taken up manually and it was under 8gb while over 90%). I constantly have this problem and never browsed through task manager much before so I am not really sure when the problem arose.


Here are some screenshots showing my comp specs and a task manager screenshot



Thanks in advance if anybody replies!