Locked Screen, how can I get in?

[AC Question]

Locked Screen

I have a samsung S5 that has not been used for 18 months.
I had a screen lock pin on it that was made up of letters and numbers. I was able to access my photos and numbers in this phone using this pin.
Today I have gone to get a number from it and the screen has changed to a telephone key pad look with numbers and letters attached from key 2 to key 9.
Everytime i try and do a letter, it gives me a number instead, and there does not seem to be a way to change it back from letters to numbers. (2abc, 3def, 4ghi) I need letters first and then numbers.
I called Samsung and they said they couldn't help me over the phone and that i had to have it picked up by courier and sent to N.S.W as there was no dealer in Perth. I dont want to do it if they are only going to factory reset it as I would like to keep my information on the phone.
Can someone please help me. i know my password.
I do not have a google account set up, and the phone is not network active.
Can a factory reset be done with an active $2 sim from the same carrier, and then use a software program to retrieve all my photos texts and info again?

 

[B. Diddy]

Welcome to Android Central! So you're saying that originally, you had an alphanumeric password screen lock, and now it's suddenly asking for a numeric PIN? You could try using a basic USB keyboard connected via OTG cable, and see if the keyboard allows you to enter the alphanumeric password. But if it's expecting a numeric PIN, then it won't help.