Help! Unable to reply to SMS messages with problem of converted '+' to '010'

[AC Question]

I have an unlocked Android phone (sharp aquos SHF31) that I am using in the States. I am able to receive messages just fine using the standard default SMS programme. I am unable to directly reply to messages as they come in with < + phone number here> and not just <phone number here>. I am able to send a message going through my contacts and sending a new message each time, but when I try to reply direct, a window pops up saying

converted '+' to '010'

This prevents any direct reply. Does anyone know how I can change this? Some way get rid of the + or stop it from changing the + to 010?

 

[the tall guy]

Hi, was your phone bought in the US?

 

[j_t_w]

OP here. My phone was not bought in the US, hence my issue. That and the fact that while I'm great with computers and programming, this is my first phone with any data capabilities. I don't even know how to get to the code portion to even take a look at it.

 

[Rukbat]

"+" means "country code follows". The phone is converting a phone number with no country code to one with a country code (even if there is none), Try adding country codes to all your numbers. (It won't hurt making a call when you're in that country - the country code will just be ignored.)

 

[j_t_w]

Already tried that. Did not help.

 

[j_t_w]

Phone was bought in Japan, is set up in English. Android 4.4.4, unlocked and with AT&T service. I have checked every setting I can possibly think of. I figure it's just some simple lines of code that need to be altered, but I have absolutely no knowledge of how to do any of that on a phone (my knowledge is strictly computer based...and yes, I do know that it's just like a mini-computer, but I lack familiarity with accessing such things on a phone).