International SMS issue with S4

[edod27]

If anyone could help, it would be much appreciated!

I have a 4G LTE Galaxy S4 that I brought over with me when we moved to the UK.  It is not locked, but it does have the Verizon software on it.  Once I got over here, I tried a sim card from a local provider, added the APN settings for the network, and voila, I had voice, data and SMS.  Only problem is, I can't reply to SMS without re-entering the number because when people text me, the phone's software automatically adds the country code and drops the leading 0 from the cell number.  Which means that if I want to respond, I need to write down the number, and then open up a new message window, type it in, and then I can respond (if they reply again, I have to rinse and repeat).  It is really going to be a problem since I am hoping to use the phone for a couple more years.

Here are things I already tried:

-Turned off internationally assisted dialing

-Turned internationally assisted dialing back on, but edited the country code to add the plus. Then edited contacts to make sure they also had the plus.

-Deleted all of the contacts and messages that had the country codes added after changing settings to make sure that the sim or phone memory wasn't causing the problem.

-Checked the Andriod forums.

-Tried other UK service providers (3, O2, T-Mobile, all the same problem)

I am out of ideas, and I don't want to give up on an otherwise functioning phone, but this pretty much prevents me from using the phone for regular texting.  I went into a mobile shop today and they said that it was likely I needed to change the mobile center number stored on the phone.  They thought it was easy, but couldn't find the setting to change on my phone.  I also searched Android forums on how to change the mobile center number, but the directions given don't seem to apply to the software on my Verizon issued S4.

Any thoughts or ideas would be most appreciated!