Magento 2 MiBPHP fatal Error

I am working on my Magento 2 and when i run the setup:di:compile commant i am running into the following message ( see screenshot )

I have opened this directory to open the file and check line 20 for myself.

This is the part of the line the error is reffering to :

class SetShippingAddressOnCart implements SetShippingAddressesOnCartInterface

I dont know what to do here i am not way too familiar with magento, any tips wil be appreciated.
if i need to post full code of the file let let me know