CEDARBURG, Wis. — A Cedarburg jewelry business is facing backlash from customers who say they paid thousands of dollars upfront for custom rings and never received the finished products.
Katie Smith contacted TMJ4's Lighthouse Investigative Team late last year after she paid MKB Jewelry and its owner, Matt Montonati, for a custom engagement ring and wedding band.
"We got engaged in August of 24, married in May of 25," Smith said.
For Smith, the purchase was never about having a flashy ring, but rather what it symbolized.
"I reached out to MKB cause they had advertised doing custom work, so I had reached out and said, 'hey, I wanna get my set soldered, potentially do something custom if the soldering doesn't work,'" Smith explained.
She met with Montonati at the MKB Jewelry storefront in downtown Cedarburg to discuss the design and price.
An invoice shows Smith paid $3,717.03 upfront for the work on June 26, 2025.
"He like showed me a couple of different designs based on what we talked about in person, and eventually got it right where he sent me an AI-generated kind of configuration of what the ring could or would look like," Smith said.
Watch: Jewelry business under fire after customers say they paid thousands for unfinished rings
The invoice detailed a four-to-six-week timeline for completion. It also included a disclaimer stating the business was not responsible for delays arising from supply shortages or shipping issues.
"I didn't hear from him the entire 4-6 weeks," Smith said.
Smith reached out to Montonati on Aug. 11.
"I reached out like the first Monday after the six-week time frame had passed," Smith said.
The next day, Montonati texted Smith, blaming supply chain challenges and promising updates. When asked if she ever received those updates, Smith was clear.
"No," Smith said.
Over the next two months, Montonati gave Smith six different dates for when her ring set would be completed, stretching into November.
"I said, 'please stop telling me you'll update me tomorrow or next week, and then just ghost me until I call your office. I need to know if the ring is actually being made or if you can just stop everything and give me a refund.' No answer," Smith explained.
At the end of October, Montonati sent Smith a settlement and completion agreement. The document stated her rings would be ready for pickup on or before November 10, and if they were not, a full refund would be issued. However, the agreement came with a catch.
"So he wanted me to sign a legal contract saying that he would only give me my rings or a refund if I promised to remove my Google review and Facebook post about this business," Smith said.
"How did that make you feel in that moment?" Chief Investigative Reporter Jenna Rae asked.
"Threatened, threatened. That felt like a threat. I simply wanted him to be responsible for what he was doing," Smith responded.
Smith refused to sign the agreement.
Instead, Smith showed up at the MKB Jewelry storefront on November 10, the day her rings were supposed to be finished per text messages and the contract Montonati had drafted.
"I went in, and the first thing he does is he says 'come on in, come have a seat, I wanna talk about what I'd like to change with your set,'" Smith said.
Smith said the rings were still not finished.
Thirteen weeks after her ring set was supposed to be completed, Smith walked out of the store with two rings, not soldered with mismatched stones.
"That was supposed to be a resolution day to finally have it all said and done, and to have to still deal with it on the day I thought it was going to be over was just more frustrating, more disappointing," Smith said.
During their months of communication, Montonati told Smith he would partially refund or compensate her for the wait, but that never happened.
"Why was it important for you to share your story about this?" Rae asked Smith.
"I just didn't want this to happen to anyone else, and I was also partially in disbelief that I was the only person this was happening to," Smith answered.
Smith wasn't the only one. However, other MKB customers we talked with did receive some sort of resolution, like Megan Lampman.
Lampman's husband got her engagement ring from MKB Jewelry in 2023. Everything then went smoothly.
So, the Lampmans returned back to MKB for their wedding bands. However, this time, it didn't go as planned.
"It's not just a normal piece of jewelry. It's our wedding bands, so it was awful, very stressful," Lampman said.
Lampman said her husband paid MKB Jewelry $5,000 for wedding bands in March 2025. However, they didn't receive any sort of invoice or confirmation receipt.
Lampman showed TMJ4 News text messages to and from Montonati, MKB's owner.
Text messages and call logs show Lampman and Montonati going back and forth for nearly an entire year. When it came time for their destination wedding, Lampman says Montonati didn't come through.
"Did you have wedding bands at your wedding?" Rae asked Lampman.
"We ordered some on Amazon," she responded. "It made me very sad cause like this is the ring that we're getting married in, and it just has no meaning now."
Months after their wedding and persistent messages to Montonati, Lampman said they received a full refund, via Zelle, but still had no wedding bands.
"We were fortunate enough to get our refund, but I know others are still waiting for answers," Lampman added.
TMJ4 News exchanged several emails with Montonati over the past two weeks, asking for an interview.
He said he is in the process of closing down MKB Jewelry and that the "overwhelming majority of customer matters have been resolved." He asked us to reconsider pursuing the story, but never set a date for an interview.
Court records show MKB Jewelry owes more than $15,000 in state taxes dating back to 2023.
A spokesperson with the Department of Revenue said MKB Jewelry met the requirements to apply and receive a temporary seller's permit, despite Montonati stating he is in the process of shutting down.
"I wish more people were vocal about it because then maybe it could've saved me and all those other women the time, the money, the emotions, the frustration," Smith said.
If you are an MKB Customer waiting for a resolution and want to tell your story, email Jenna Rae at Jenna.Rae@tmj4.com.
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