The Block's Luke and Jasmin suffer 'monstrous mistake' a day out from reveals

There have been a few ups and downs on The Block already this year, with teams facing serious issues.

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But it looks like disaster is about to hit Luke and Jasmin in House 4, with the newest promo for the show teasing a bit problem.

"We found [Foreman] Dan in the room and my heart just sunk," says Luke.

The voice-over says that the teams are just one day out from reveal and it looks like there's going to be a big problem for the couple.

"Your worst nightmare just happened," Foreman Dan tells them.

A clip then shows Luke in the front yard of the Block homes, storming over to the foremen.

"No one [bleep] told us," he fumes.

Foreman Dan replies, "We did mate, we did."

"No one told us," Luke blasts again, letting out a few expletives as he walks off.

Whatever the issue is in House 4, it's not looking good for the couple finishing their upstairs this week.

"What is the monstrous mistake that leaves one Blockhead ripping up their entire floor," says the voice-over.

Footage plays of Luke and his team ripping up flooring, but Foreman Dan is back to deliver more bad news.

"I've spoken to Scotty, can't be revealed until it's fixed," he says.

They're just one day out from reveals so this is going to be a huge setback.

But what exactly have the couple done wrong in House 4 to put them in this position so late in the week?

The Block airs Sunday at 7.00pm and Monday to Wednesday at 7.30pm on Nine. Catch up on all the latest episodes on 9Now.