I already help you renamed this duplicate language file from JoomlaFOlder/administrator/language/en-GB/en-GB.plg_app_user_blog.ini , it should work fine.
You are most welcome. Glad to hear that your issue has been resolved now.
As a gentle reminder, kindly start a new thread if you have any other issue in the future so it will be easier for us to manage your inquiry. I will lock and mark this thread as resolved.