im using

Difficult to help if you dont give any more info. Traffic type/source?
Im using f5 media through decisive its a sweepstakes for india
Hey Phantom, this is common when running camps from mobile traffic sources. Try filtering the camp by Publishers (site ID's?) and usually you will find that most of those duplicated IP are coming from a few publishers. You can block the bad publishers. I haven't run with Decisive but I know they allow you to do this.
You can always talk to some representative from the traffic source, send them an email or add them on Skype. You need to keep good communication or you will lose money when running from mobile sources.
I lost $1.3k in a few mins from a mobile ad network.. just because I didnt target any browser, huh.
If it's mobile traffic then I'm not sure that this is a problem.
In fact it's completely normal.
Carriers must aggregate 100's if not 1000's of devices to the same IPs.
If you didn't have a lot of visits from the same IP addresses then that would be abnormal.
Just use your investigative mind here. Drill drown by carrier > placement > device or similar and you'll see quite clearly that there must be lots of unique users with the same IP, otherwise the data wouldn't add up.
Of course you can and will find bots too, but they are a minority.