The Federal Communications Commission said on Tuesday it had received numerous complaints from consumers that Comcast added charges to their bills for unordered services, including premium channels, set-top boxes, and digital video recorders.

Comcast (CMCSA) will implement a five-year compliance plan as part of a consent decree, the FCC said, and must offer a detailed program for responding to consumer complaints “in a standardized and expedient fashion.”

By next year, the FCC said, Comcast must send customers a separate order confirmation of new services, allow customers to block additional cable services, improve customer record keeping and require additional employee training for individuals placing excessive unauthorized charges on customer bills.

Comcast spokeswoman Sena Fitzmaurice said the company did not agree with the FCC’s legal theory but added, “We acknowledge that, in the past, our customer service should have been better and our bills clearer.” She also said Comcast had already committed to make most changes sought by the FCC.

The FCC investigation found numerous examples of Comcast billing customers for services they did not want but would not refund charges. Customers were often told by Comcast that the company would only address six months of billing issues because of its computer systems, the FCC said.

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In June, a U.S. Senate panel found overbilling to thousands of consumers by Charter Communications (CHTR) and Time Warner Cable, which has since been acquired by Charter.

The Senate’s Permanent Subcommittee on Investigations said the companies made no effort to trace equipment overcharges unless consumers asked and did not provide notice or refunds.

Comcast told the Senate panel it would make it easier for consumers to cancel service without being forced to stay on the phone and answer questions.