setDataInrow=allLine.split(";");
You do this once for each line. But you don't split the line, as you intended, but each time the whole file content.
Edit: Don't split allLine. You have already a QStringList, which contains your lines: rowNumbers.
This you must split.
for(int row=0;row<rowNumbers.count();row++){
QStringList rowCells = rowNumbers.at(row).split(";");
.....
}
I hope this gives you the idea. No guarantee for details.
Edit 2:
When you do
setDataInrow=allLine.split(";");
your stringlist contains:
John Kl 34 1335532 CA 0444344 Kuma jo 54 44432 NY 0322355 Lebal ho 24 44022 NY 0110004.
This is the whole text in your file. The line breaks do not matter. They are just another character. You add all this in one row. And you do it three times.
What you want is first split the text into lines. You already do this here: rowNumbers=allLine.split("\n");
With your example data the rowNumbers stringlist contains three entries. Each entry one line from your file. These lines you have to split.