"It wasn't even a discussion — that's their protocol, to deny you right away," Kenneth says

Armando Rubio and Kenneth Niedermeier just hit another heartbreaking roadblock on their journey to get married.

In PEOPLE's exclusive sneak peek at Sunday's episode of 90 Day Fiancé: The Other Way, Armando, 31, and Kenneth, 57, attempt to get approved for a marriage license in Mexico. The two are the first male gay couple on the TLC franchise.

"Kenny and I have been talking about marriage for some years now," says Armando. "It's something we want, something we dream of. Today we are ready to make that a reality. We are going to the marriage office to apply for our marriage license."

When they get to the office, Armando presents the civil registry clerk with the proper documentation they were told they needed in order to obtain the license. But the meeting quickly takes a devastating turn.

"We have to give you a negative answer," the clerk says, in Spanish.

Kenneth and Armando, 90 Day Fiance
Credit: TLC

Confused, Armando explains that he read online that same-sex marriages were, in fact, legal.

"In this case, we have a law that states, 'No you, can't,'" the clerk explains. "And we have a constitution that says, 'Yes, you can.' Sadly, we don't have legislation that supports us to reform our code. The one that says we still can't allow same-sex marriage to go through."

When Armando relays to Kenneth what the clerk said, he becomes emotional.

"I did look up online and it did say gay marriage was legal in the state," says Armando. "I'm really not understanding all that she's saying, because things seem to contradict each other. In reality, I'm confused myself."

"I don't think even seven words were spoken and it was 'denied,'" Kenneth adds. "It wasn't even a discussion. That's their protocol — to deny you right away."

Armando and Kenneth met through a gay fathers support group and immediately hit it off. After falling in love, Kenneth made the decision to move to Mexico to start his life with Armando and his daughter.

90 Day Fiancé: The Other Way airs Sundays (8 p.m. ET) on TLC.

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