Why did it happen all of a sudden?
How do we know.
It's your system.
It's your code.

You only show two lines of it yet you expect us to answer your questions!

However you did say that you are splitting comma seperated values (without using one of the fine modules from CPAN).

So I'd have to say that you are probably splitting a quoted section that has an embedded comma.
blah, blah,"ha ha! I've got an embedded comma,",blah,blah
You can't do that and expect it to work right.

I recommend Text::CSV or Text::CSV_XS for the job.

By the way, an extra; ;
now and then shouldn't hurt your code;;
provided it's at the end of a line; ;
and not in the ; ; ; ; middle of it.
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