InvalidCastException: Cannot cast from source type to destination type

I tried to do a SaveManager that saves and loads the users data,
for some reason it saves it but i think its finding it hard to load it

I upload the code to to a website

heres the error
InvalidCastException: Cannot cast from source type to destination type.
SaveManager+c__Iterator3.MoveNext () (at Assets/Scripts/SaveManager.cs:85)
UnityEngine.MonoBehaviour:StartCoroutine(String)
SaveManager:Awake() (at Assets/Scripts/SaveManager.cs:36)

heres the link with the code

If anyone can take a look and maybe help debug this and find the issue i would be very thankfull.

Haven’t tested your code, but try this:

Instead of doing:

P1_string = (List<string>)o[3];

Do this:

P1_string = o.Cast<string>().ToList();