Internet not working on Samsung Galaxy S2

[#1]

Internet not working on my Samsung Galaxy S2 after taking the sim out for a few weeks and then putting in back in today. The whole phone says it's connected to the O2 line and not giffgaff, what settings do I have to change? Anyone any idea?

[#2]

Hi ,the easiest way to get the giffgaff Internet on your phone is by sending a text with the message “SETTINGS” to 2020 ,if you use this service please re-check your settings afterwards for one wrong entry (please check & edit the browser Proxy IP address to Blank if there )  

but if that doesn't work for your phone then you could try the following

As your phone is an android based phone you maybe able to use an app from the play store to install the giffgaff APN settings ,see the link below

https://play.google.com/store/apps/details?id=com.paulshirley.android.giffgaffsetapn

Or you could install an android giffgaff app

https://play.google.com/store/apps/details?id=com.qmusa.giffgaffapp&hl=en_GB

If that doesn't work on your phone then

you could look to see the internet settings for most androids here and add them manually to your phone

Go to Settings.

Choose More Settings.

Choose Mobile networks.

Choose Access Point Names.

Press the Menu button on your phone and choose New APN.

Tap Name and type giffgaff, then tap OK.

Tap APN and type giffgaff.com then tap OK.

Tap MMSC and type http://mmsc.mediamessaging.co.uk:8002 

Tap MMS proxy and type 82.132.254.1

Tap MMS port and type 8080

Now press the Menu button on your phone again, and choose Save.

Tap the little circle to the right of the profile named giffgaff on the list. It should turn green.

Your phone is now set up for giffgaff's internet and MMS settings.

[#3]

Hi
Send "settings" to 2020 if that would not help you then find Top Tips in the link below please
http://community.giffgaff.com/t5/giffgaff-Top-Tips/Giffgaff-internet-and-MMS-settings-for-Samsung-Ga...

[#4]

02 and gg are together btw. Try texting settings to 2020 and follow instructiobs.

[#5]

Simply send the word "settings" to 2020 and this should have you back up but you can also find a ton of guides in the help section and there is also a nice thrid party app called giffgaffapn which you can get from the market