I'd do one of two things-actually, I'd do both:
1. contact the store where you purchased it.
2. Look on the internet, see if there's a website for Congoleum.

I have Marmoleum in my kitchen, it's about 3 tears old-similar to lineleum or Congoleum. I sweep daily and then go over with a Swiffer WetJet. About once a month I get down on my knees and do the edges and any spots I missed with a scrubbrush and liquid cleaner & water. It still looks like new.

Here is the page on their website that has info on cleaning. Oddly, they don't specifically mention your product, but it appears that they want you to use their Bright 'N Easy No Rinse Cleaner.

Here is a link that might be useful: Congoleum

Thanks. I'll do that.