6/4/24 -- Josh's company, Preview Models, tells TMZ they worked with Sharaun and did everything in obtaining and using her image on the up and up -- but claims they got a letter from her in November that demanded money over what she felt was an unauthorized use of her likeness.

PM also says that any unauthorized materials pertaining to Sharaun were destroyed, and that they haven't heard a peep from her ... until now. Preview Models also tells us they haven't even been served with any papers pertaining to this suit ... but note that if/when they officially become aware of it, they'll defend themselves ... and might even countersue her if need be.

"90 Day Fiancé" star Josh Weinstein is being dragged to court by a model ... with her claiming his production company used her image to market his business, but is not paying up.

Sharaun Brown just filed a lawsuit against Josh, claiming the reality star's Preview Models production biz used her photos on its website to promote the company, propping her up as a "Celebrity Mentor" and using her to lure in aspiring models.

According to the lawsuit, obtained by TMZ, Sharaun says Preview Models started using her image around February 2023, adding her photos to ads for open casting calls, fashion shows and booking services.

Josh's company promises aspiring models a chance to get on a runway in front of top modeling agencies in Los Angeles ... and Sharaun claims the company is using her fame to give the biz some legitimacy among models.

Problem is ... Sharaun says Josh agreed to compensate her for using her images in educational and marketing materials, but Sharaun says he hasn't paid up.

In the docs, Sharaun says after Josh never followed through with the money, she requested Preview Models stop using her image in any form around May 2023. She claims Josh's biz is making it look like she endorses the company when in reality she does NOT.

Sharaun is suing for unspecified damages for the unauthorized use of her images and for violating her right of publicity.

We've reached out to Weinstein ... so far no word back.