Samsung S7 Edge Keyboard not working properly in email text? HELP!!

[AC Question]

I have a Samsung Galaxy S7 Edge. Just suddenly my keyboard is not working properly. Its the weirdest thing ever. Usually when typing an email, when i tap the space bar twice, it will insert a period and capitalize the first letter of the next word. Well only in the email text (it works fine in the email subject line), does it not work any more and its driving me insane because I use my phone a lot for email. Is anyone else having this issue? I have done a factory reset and reboot but still same issue. I even exchanged the device for a new S7 Edge and its doing the same thing on this one. It must be some glitch thats copied over from a previous device but how do I fix this? Please help! Thanks.