Help APN (Access Point Name) gone after changing MNC (Mobile Network Code) => No 3G connection!

[GShum]

In order to get a 3G/internet connection working, one needs to create a APN (Access Point Name) entry.

I've created this APN entry (copy/pasted from an "APN backup xml file):
<apn name="hollandsnieuwe int." numeric="20404" mcc="204" mnc="07" apn="data.dataxs.mobi" user="" server="" password="" proxy="" port="" mmsproxy="" mmsport="" mmsprotocol="null" mmsc="" type="default,supl" />

But when I change it from MNC=07 to MNC=04 (the one I need) and save it, it's is gone!
If found (with Google) that this happens a lot, but a solution I could not find.

The problem is (I think) because for some reason my phone thinks it is a "provider Teleena MNC=07 device" (that is what Google's Market/Play displays).
Do you know of a method to change this?

Software like "APN Backup & Restore" does not do the trick.

Thank you very much for any assistance.

 

[GShum]

Problem solved!
I guess I'm lucky because this probleem can be a really tough one to solve.

My solution. I simply overlooked a new app that came along with the new simcard (from my new provider). With this little app I had to change a few settings before I could create a new APN.

Starting the app: Select Roaming services => Select Mode => Select Manual => Select International. After this, the simcard was updated.
Now I could succesfully create a APN with the ever-needed MNC=04.