My cell service and data is not working

You see, I cannot connect to my data so I am unable to send and receive calls along with text messages. I also can't access my data, which my provider is not the problem and I know that because my other family members (who I am on the same plan as) are not having a problem. I think it is because my phone is just about 2 years old and is very cracked, plus the battery and back have popped out plenty of times in result of dropping it. I am thinking of doing a hard reset to see if that would help, but I do not want to loose the files on my phone. Please help?