Tech support syndrome

When an issue in a computer seems to be fixed when you are on the phone with tech support, but as soon as you are off the phone, the issue comes back full fledged.

Britney: Is your computer fixed?
Alyssa: No, its acting weird still.
Britteny: Wasn't it working when you were on the phone with John before today?
Alyssa: Yes, but its not working anymore. It stopped working as soon as we hung up.
Britteny: I guess your computer has tech support syndrome.
Alyssa: Yeah.