T-Mobile’s hyped move to “un-cable” the pay-TV bundle has run into the buzz saw of the cable industry’s distribution contracts. And now the wireless carrier is being forced to rethink the pricing and packaging strategy of its low-cost TVision streaming play.

On Nov. 1, it launched several new TVision “skinny bundles” aimed at cord-cutters, initially available to T-Mobile postpaid wireless customers. One of the key attractions, according to the company, is the way it has assembled channels to provide more choice for consumers — its cheapest tier is TVision Vibe, which for $10 per month includes 34 lifestyle, comedy and entertainment networks (keeping the costs down by stripping out sports, news and local TV stations). Separately, it’s offering three “Live TV” tiers, starting at $30 per month, but those don’t include any of the channels in Vibe. (See the current TVision channel lineups at this link.)

“It’s everything you love about cable and streaming services, minus the stuff you don’t,” including “expensive bloated packages just to get the channels you really want,” T-Mobile said in announcing the new streaming services.

The problem: T-Mobile’s unconventional re-bundling isn’t allowed under the carriage deals it signed for TVision, according to several media companies. As a result of the pushback, T-Mobile will likely have to rejigger the lineups of its over-the-top TV packages, which are priced lower than rival services like YouTube TV and Hulu + Live TV.

That could mean T-Mobile will eliminate the super-cheap Vibe, or that it will need to stuff more channels into TVision Live TV — both of which are outcomes that threaten to puncture the main value proposition the company has touted.

“The way they’ve structured this, it’s just a no-go,” said an exec at one of T-Mobile’s programming partners. The source added that T-Mobile has “a time period of a few weeks to rectify the situation.”

Discovery chairman and CEO David Zaslav publicly raised a red flag last week about T-Mobile’s TVision. On the programmer’s Nov. 5 earnings call, he said, “We were very surprised with how T-Mobile decided that they were going to bundle our networks, particularly because we have a clear agreement where our networks are required to be carried on all their basic tiers.”

Zaslav said Discovery was “in active discussions with them to quickly resolve that issue.” He continued, “We don’t believe they have the right to do what they’re doing right now. And they know, it’s very clear to them, and they’re focused on it.”

Sources confirmed that NBCUniversal and ViacomCBS have conveyed objections to T-Mobile similar to those raised by Zaslav, as previously reported by CNET. A source familiar with WarnerMedia said its team is in the process of looking into T-Mobile’s TVision bundles — and that the media conglom does believe there’s a case to be made that the wireless carrier is in breach of contract. Reps for those media companies, as well as AMC Networks, Fox Corp., and Disney, declined to comment. A Discovery rep declined to provide additional info beyond Zaslav’s comments.

A T-Mobile spokesperson declined to comment on what specific changes to TVision are on the table.

“We are of course complying with our content agreements, and we are absolutely open to evolving our services to make them even better for consumers. We are just getting started,” the T-Mobile rep said, adding that the carrier wants “to be a great partner to media companies.”

As Zaslav noted, standard TV distribution deals specify that a certain set of a media companies’ channels must be included in a pay-TV provider’s most basic tier. There are two issues with how the TVision bundles are put together: First, the Vibe package — which at the $10 price point can be considered its entry-level tier — does not include local TV networks or many basic cable networks. Second, the networks in the Vibe lineup aren’t included in the TVision Live TV options (normally, everything in the “basic” tier is included in more expensive ones).

For T-Mobile, shifting channels around in the different tiers to accommodate the cable programmers’ standard agreements could result in fatter — and pricier — bundles.

T-Mobile CEO Mike Sievert, on the carrier’s Q3 earnings call with analysts Nov. 6, acknowledged that some media partners “would like to see changes” in the TVision packaging. “We’re working with them because we’re open-minded,” he said. If the changes media companies are demanding “are great for customers and help us continue to smash customer pain points, we’re open-minded.”

Sievert also suggested that T-Mobile isn’t looking at making money on TVision, per se. Instead, he positioned the over-the-top pay-TV service as a kind of customer perk designed to drive subscribers to 5G wireless.

“This is a business that isn’t really a business,” Sievert told analysts, speaking about TVision. “We’re in it for the long haul but we’re doing it to delight customers, and we’re doing it to set up a home broadband business, which is going to be where a big piece of the profit pool is.”