How do I change my lockscreen security back to swipe?

[Bluefield]

I have a galaxy s4 on Android 5.0. My lockscreen security has always been swipe, but I changed it to PIN. Now I want to change it back to swipe but the option is greyed out with message "disabled by administrator, encryption policy or credential storage".
I've read on another thread that the way to get the option back is to clear credentials in security, but also that this is unwise to do.
In security, device administrators, I have Google device manager ticked, but deactivating this doesn't ungrey swipe.
There also doesn't even appear to be an option to change the PIN code.
I've never had a VPN set up and the phone is unlocked. I also have never set up any kind of password for the lockscreen.
Am I missing something obvious?

 

[vjh425]

Do you have a work email on your phone? Some jobs I've had have email that require the phone to be secured with a pin.

 

[Bluefield]

No work email, phone is personal use.
From reading around, I managed to find a fix, without using the clear credentials option.
On the lockscreen security options, choose pattern, then add a back up PIN when prompted. Next, open lockscreen and enter incorrect pattern five times until you get the 30 sec lockout. Enter back up PIN, go back to lockscreen security and press swipe option (still greyed out). Go back a screen and the method will show as swipe again.
You shouldn't have to mess around doing this, but at least it works without having to clear credentials.

 

[GeorgeParrish]

No work email, phone is personal use.
From reading around, I managed to find a fix, without using the clear credentials option.
On the lockscreen security options, choose pattern, then add a back up PIN when prompted. Next, open lockscreen and enter incorrect pattern five times until you get the 30 sec lockout. Enter back up PIN, go back to lockscreen security and press swipe option (still greyed out). Go back a screen and the method will show as swipe again.
You shouldn't have to mess around doing this, but at least it works without having to clear credentials.

 

[GeorgeParrish]

This method of entering your unlock pattern incorrectly 5 times and then entering your PIN correctly, going to the Lock Screen settings and pressing the SWIPE button (even though it's Grayed Out) actually works! I just tried it and now I have my SWIPE SCREEN is back!