As much as I hate to admit it, I’ve been in modern technology for a long, long time. One thing I’ve learned is that about 90-percent of all wonky devices can be fixed simply by turning it off and back on again.
David Nield backs me up with a big long list.
Resetting a device used to be an absolute last resort, such was the associated hassle in getting everything back working again. Nowadays, everything from apps to contacts to photos is (usually) stored in the cloud, and can be synced back again relatively easily.
That’s my first recommendation to anyone.