Amid recent reports of Verizon Wireless customers getting dinged on their phone bills with unexpected data overages, it may come as no surprise that the Federal Communications Commission has seen a spike in complaints related to the company.

Verizon customers filed 2,079 federal complaints against the company over billing in September, The Cleveland Plain Dealer reports.

That might not mean much, until you take into account that more complaints were filed in that one month than had been filed in the previous eight months of this year: according to the FCC, customers submitted 1,442 complaints up through Aug. 31, about 180 a month on average.

The sharp uptick can be attributed thousands of customers are reporting inexplicable increases in their data, The Plain Dealer reports, citing interviews and figures it obtained through the Freedom of Information Act. The paper analyzed monthly totals filed against Verizon for this year through the FCC, and found that in January, customers filed 278 complaints against Verizon, which was the most filed in any month through August. Then came September, and the total jumped to 2,079, a 648% increase from January’s figure.

“That’s an incredibly large leap,” Bruce Kushnick, the executive director of New Networks Institute in New York City, which tracks and analyzes communications companies and services, told The Plain Dealer. “If the Federal Communications Commission doesn’t investigate what is going on here, something is wrong. This is just the tip of the iceberg. You have to wonder whether this has been done on purpose.”

It’s not just Verizon that’s getting hit with billing complaints: there were 2,656 complaints filed against all wireless carriers from Sept. 1-22, The Plain Dealer notes, up from a total of 746 such complaints filed last year at the same time.

The FCC’s online data doesn’t break down complaints by company, so the paper requested those figures regarding Verizon by submitting a FOIA request.

We still don’t know what’s causing the uptick in data overages, and thus far, Verizon is staying mum on the topic. Some Verizon customers say they used to receive alerts when they were close to going over their data, but those notifications disappeared.

A rep for the company previously told Consumerist that users can opt in to receiving alerts once they’ve reached 75% of their data usage, but automatic alerts doesn’t kick in until you reach 90% of your monthly allotment.

“All Verizon customers receive a text alert on their device when they’ve used 90% of their plan data in a month and then again when they’ve hit 100% (which indicates they’ve gone over),” the rep told Consumerist. “In addition, customers can also better manage their data use by opting in to a 50% alert and a 75% alert.”

Verizon’s billing issues spur large spike in FCC complaints [The Cleveland Plain Dealer]

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