How do i change the battery and change dials - Fossil FS2919 Wrist Watch

take it to a watch shop

use battery in it to find out

You should change the battery, it is the cheapest thing to try. The batteries can be very old before they are installed and could have been in the watch a long time before you got it.

battery in backwards

you need to push the crown or winder in before it will work

reset, by checking the mode, select, set. if not contact manufacturer for assistant.

I contacted the manufacturer. You remove the crown, then use tiny attachment to a bike pump to push air into the interior of the watch. This will cause the crystal and dial to come apart. Viola!

You have to dismantle your watch first.
Check the back of case- if there are visible screws- undo them and take caseback off. You should see the battery. Take it out, read the numbers on battery and replace with the same one.
If you can not find any screws on caseback- you have to undo screws from the dial side, get the movement out and then change the battery.
BE WARNED: if the watch must be opened from dial side, you can easily damage it as some particular skill is needed. Do it on your own risk.

Good luck