I have not been given the package I have asked for

I ask that my contract must be migrated from an open line to a top up with the terms that I will get the same packages as I am getting on a open line, which was to get 2Gig during the day and 3Gig at night. I was told that I will get it starting from the 1st of February but now when I call customer care to inquire about it they say I can only get 2Gig during the day.