Is this supposed to happen?

I recently bought my 360 Elite and GTA IV which means I am a new 360 user. I played GTA 4 on my own profile and my brother made his own profile and played GTA. Then I went back to my profile without turning of the 360 (but I was at the dashboard), and I went to GTA and it started from the beginning. It didn't start off where my brother saved on his profile it started off at the beginning. Then I turned off the system and turned it back on and my data still wasn't there. Then I played online and came back and my data was all there. Then my brother went back on and saved and my data was gone again! Then I turned off the 360 and turned it back on and my data was there. Is that supposed to happen? Should I tell my brother to stop saving?Is this supposed to happen?
So, you're saying you try to load data from your brother's profile so you can start where he left off, but you're in your profile. I think I know what's happening. If you brother's profile is the one with online capability then it is the default profile picked when you go online, so when you got done, you were still in your bro's profile then you load his data and you start where he left off.Is this supposed to happen?
My Profile is the Xbox Live one. When my brother is done with his profile, I load mine and all my data on my profile is gone. Then I restarted the system and it came back. This happened twice. And when my data was gone on my profile it didn't start where my brother started off, it restarted from the beginning.
Anyone know this problem?
prbly a mix up of two gamertags, two profiles on gta
So can my brother keep saving?
bro here is what i geti have wireless controller roomate has wired controller no matter who plays last it will default to the wired controller. so that is one issue. i have also seen your issue but usually by quitting the game and coming back its fine. alot of the issues i have seen pertain to having something in the usb ports/controller ports.
Yeah, but we have 2 wireless and we used the same ones.

sun sunscreen