Yes, I am using the default phone app. Apologies for the delayed response, I was having login problems.
You aren't the only one. Took me 45 minutes to finally get logged in.
Try this. Open your contacts app. You will see the 3 horizontal bars on the left side of your screen. Click them. You will see a list of groups. At the top will be a Name of your list. Mine says Google. Click it. You will see a list, All contacts, Samsung account, Phone, Sim Card, Google, Microsoft Exchange... Your list might include none of these or just some of these. I had this happen once, where it was saving some contacts on Google, and some on Samsung, Some directly on the phone. Make sure that the list says "ALL CONTACTS" at the top. That will include everyone on every list.
See if that helps any.
It would appear that in safe mode the phone contacts screen and the contacts app screens contain the same contacts.
I am thinking what I want to do is remove the google contacts "icon" altogether if that makes sense but don't see where I can.
With your most recent comment, it shows that an application(s) was(were) installed that caused the havoc.
You have to think and remember it so that you will get rid of it....