Inspiron 3670, multiple issues

I purchased a Dell Inspiron 3670 computer and monitor at Costco on January 19, 2019. I set up the computer and twice it has broken down. I was unable to start the computer and have been on the phone with representatives of Dell and Microsoft. The most recent conversation I had with Microsoft and they wanted me to reload the Microsoft 10 operating system.
During a call with Dell, they told me the computer was not under warranty even though I bought it on January 19, 2019 at Costco. The technician told me I could buy a warranty package for $239.00 for one year. I hung up on him.
The purchase of this computer has been one of the most frustrating purchases I have ever made. Since then I have reloaded Windows 10 with the help of a Dell representative. So far, things are working after I re-installed Windows 10. Costco contacted me and said they have a 90 day return policy should anything else go wrong, and if something goes wrong again, I will return the computer and monitor to them.