Quite often, when Turing wifi calling on or off viw the quick panel, the button stops working and isn't dark, but isnt light either. It's "gray" (light blue on my current theme). Clicking it or long holding it does nothing. If I restart my phone this most times (but not always) fixes the problem, but the problem quickly comes back. I use wifi calling at work due to a lack of signal but turn it off when I'm not at work because some messages won't come through with wifi calling turned on. So, I turn the wifi calling on and off several times per week, and this issue with the quick panel button not working happens several times per week. Turning wifi calling on/off via the settings menu works.
If the Wi-Fi calling continues to turn off, we recommend having the phone evaluated by an authorized service center. You can use the following link to find a list of service centers in the U.S. that can do the repair: http://www.samsung.com/us/support/service/location or by calling customer support at 1-800-726-7864.
Try these steps. With the phone turned off, press + hold power and volume up buttons until the Samsung logo disappears. Using volume keys, highlight Wipe cache partition, and then power to select and confirm. Returning to the previous menu, use volume to navigate to Repair apps, and then power again to select and confirm if necessary. This will reindex all apps on your phone.
