Help Mobile data not working for apps

[Aston93]

My apps such as facebook and twitter work perfectly fine on wifi, but when i turn wifi off and switch to data roaming no apps can seem to make a connection, texting, emails and calls work fine, just not any apps. This is a big problem for me. I made sure data roaming is on and i cleared the data for the apps but that has not helped. I'm with Vodafone as my carrier. I hope somebody has an answer? Thank you.