'90 Day Fiance': Stephanie Confronts Erika About Finding a Dating App on Her Phone (Exclusive)

The honeymoon period is over for Stephanie and Erika.

The honeymoon period is over for Stephanie and Erika in this exclusive preview of 90 Day Fiance: Before the 90 Days' brand-new episode airing Sunday on TLC.

During the latest episode of the hit reality series, 29-year-old Stephanie traveled all the way from Yonkers, New York, to Australia to finally meet 24-year-old Erika, her online girlfriend. Although Stephanie had insecurities about being intimate with Erika after having been single for so long, and was also worried that her health issues -- she has a rare bone marrow disorder that requires clearance from her doctors to travel, as well as several medications to keep her stable -- would drive Erika away, she had nothing to be worried about. Erika said she would never want to make Stephanie uncomfortable and was OK with the two just kissing, and was also understanding about the extra precautions she had to take due to her illness.

But in this sneak peek, the two have their first fight, when Stephanie confronts Erika over still having a dating app on her phone. Stephanie says she saw the app when Erika showed her something on her phone, though Erika says she hasn't been with anyone else over the four months they've been speaking online.

"I still have one of the dating apps because there's a business networking side of that app, but I don't use the relationship side of that app," Erika, who's a photographer, says.

Stephanie asks her to delete the app and Erika does so, but is definitely annoyed.

"If you don't have faith in me then how is this going to work, you know?" she asks her.

Later, Erika continues to voice her disappointment with Stephanie to TLC cameras.

"Steph asking me to delete this app suggests to me that she doesn't trust me at all and I think she's going about this in a completely inappropriate way," she says.

90 Day Fiance: Before the 90 Days airs Sundays at 8 p.m. ET/PT on TLC.

Meanwhile, ET recently spoke to Stephanie about being part of the first-ever same-sex couple to be featured on the TLC franchise.

"I feel like there's a lot of pressure -- you don't want to let anybody down," she told ET. "You don't want to let down the LGBTQ community and a part of me wants to be, like, great representation for this community, but also I think we all just need to realize we're just like any other couple. We're gonna have just similar problems to all the other couples on the show. I hope that people come into this with an open mind and give us a chance to share our story."

Watch the video below for more: