After the update that I received yesterday, both of our Samsung S7 devices that were set to automatic time updating incorrectly changed to Mountain time zone instead of Central time zone. The only way I found to make my phone show the correct time was to switch to manual time updating and manually set the time zone to Central time zone.
There must have been more then just a security patch in that update. Someone else lost some of their apps and pics just waiting to hear from others who are having problems after this update. Have you done the clear cache partition after you got the update? Volume up -Power -Home. Then go down to clear cache partition. This will clear out all the old files and will not do anything to your phone settings. However I have read a lot of complaints on here about the time being messed up on their phones. Have you read any of them?
I know how important it is to have the correct time displaying on your phone. Clearing the Cache Partition is absolutely a great step, as provided by Kathy65793. I would recommend taking that step first, and testing for resolution. The other thing that you can do is put the phone into safe mode, and see if the time corrects itself shortly after. You can put the device in safe mode by pressing and holding the power button> when the menu pops up asking if you want to power your phone off, press and hold the "Power off" option until another pop up arrives asking if you want to place phone in safe mode> Press yes. The phone will restart in safe mode. Please try these steps and let us know what happens.
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