Lifestyle influencer Brittany Davis has amassed hundreds of thousands of followers on YouTube and Instagram with inspirational messages and fitness tips. Like many influencers, she then leveraged her following into a business by marketing customized fitness plans, diets and coaching for paying clients.

But now, she claims, her legions of fans are turning on her with "hundreds" of death threats and harassing remarks over what many of them claim are generic workout and diet plans that aren't customized for them as Davis promised.

They're making their dissatisfaction known on the very platforms where Davis developed her following. Some say she never delivered goods they bought from her. When they've complained to her, many say, she's gone silent, deleted their comments or blocked them.

Trying to respond to the viral attention, Davis took to YouTube.

"I am scared to film this video," Davis said nervously to the camera in a video uploaded to YouTube on Feb. 6.

Below the video are comments from dozens of customers criticizing Davis for not refunding money to them after buying what they describe as generic workout and diet plans.

Davis, better known as Brittany Dawn to her followers, said in the video that she has gotten death threats and verbal harassment for the past several days.

Her apology video has been disliked 14,000 times on YouTube, and social media tracking site SocialBlade shows that her accounts have lost more than 10,000 subscribers since she posted it. The description below her video, which runs 7 minutes and 33 seconds, included links to buy her fitness plan, book an Airbnb with her or shop her self-tanning products.

In the apology video, Davis appeared visibly shaken. "At times, it got extremely overwhelming and I took on more than I should have. And for that I take on full responsibility and I am sorry," she said.

Davis said she's created an email address where clients can send her complaints and proof of purchase. She promised to handle them as best she can, adding that she was "not only the coach, but also the sole content creator, customer service, business owner, YouTuber, financial adviser and everything else that comes with every business."

Nearly 4,000 people have joined a private Facebook group called Brittany Dawn Fitness Complaints, where users have been detailing their interactions with her and documenting unsuccessful attempts to obtain refunds.

Complaints about Davis have been posted on the Better Business Bureau's site dating as far back as early 2018. However, public outrage picked up steam recently after YouTube prankster Cassady Campbell confronted Davis at a fitness expo.

That spawned other videos on established YouTube accounts from followers frustrated with how Davis has handled the situation.

YouTube user and former dietitian Juicing Julianne posted one video response in which she described buying a diet plan from Davis several years ago with no issues. She said she has followed Davis since 2015.

Julianne told viewers she would have been "overwhelmed" in her former practice if she had more than 10 clients. She said Davis claimed to have 1,500 clients.

"When you work in the fitness industry, especially as a trainer or nutritionist, it takes time to develop these plans," Julianne said in the video. "And for her to ignore her clients and put them on the back burner because she was too busy ... it's just totally wrong."

Davis is not listed by the Texas Department of Licensing and Regulation as a licensed dietitian. On Tuesday morning, her website showed packages for 30-, 60- and 90-day workout and diet plans for as much as $300. By the afternoon, most mentions of diet and fitness-related products had been removed from the site.

A screenshot of Brittany Davis's website, taken Tuesday morning.

The outcry over Davis' business practices comes at a time when the social media world is discussing the pitfalls of monetizing followings, with no real plan for scaling up a business or, worse yet, outright fraud.

Documentaries about the disastrous fraud that erupted from Billy McFarland and Ja Rule's Fyre Festival have captivated audiences on both Netflix and Hulu. And just last month, Instagram influencer Caroline Calloway came under fire for a "tour" in which followers could pay to meet her and which many of those same followers say didn't deliver on what was advertised.

"Deleting comments and blocking users is a major issue, and that's something that Fyre Festival engaged in," said Caitlin Mitchell, a social strategy director at Dallas advertising agency The Richards Group.

"Social media is both a blessing and a curse. It's a blessing in that you can build and scale your business faster than ever, but you can also completely destroy and tarnish your brand faster," Mitchell said. She believes it's going to be "very challenging" for Davis to rebuild her brand and reputation.

"Once you've lost transparency, everything is lost," said Mitchell.

Davis' business is listed on the Better Business Bureau as residing in Whitesboro, a town in Grayson County north of Dallas. Her YouTube apology lists a P.O. Box in Sherman. She did not respond to phone or email requests from The Dallas Morning News for comment.

The Better Business Bureau said it doesn't have any more recent complaints against Davis, other than the six published on its website from 2018. None are from North Texas. She has an "F" rating for not responding to complaints, a BBB employee said.

Over 8,000 people have signed a Change.org petition to "dissolve the Brittany Dawn Fitness brand." The petition indicates its goal is to "save women from unethically curated fitness and nutrition programs as well as to protect future potential customers from further instances of fraud."

Davis' statement accompanying her apology video pleads with her followers to end the harassment.

"Unfortunately, with being human, comes learning from making mistakes," it said. "This is my heartfelt apology, to move forward and make things right. And I please ask that the death threats end, and for my family/friends to be left alone from here on out."