Frontier Communications will pay restitution of $750,000 and spend $10 million to upgrade its broadband network to settle an investigation by the Minnesota Attorney General's Office over customer-service problems.

Frontier has been under fire from Minnesota consumer and telecommunications watchdogs for the past couple of years after a deluge of complaints about its phone and internet service.

The Attorney General's Office was investigating possible deceptive market practices related to Frontier's internet services.

With the settlement announced Monday, Frontier agreed to fully disclose its prices for internet service to new customers and allow many current customers to cancel their service without penalty.

"For so many folks, especially in Greater Minnesota, affording your life means being able to rely on the promises your telecoms provider makes for the internet service you depend on," Minnesota Attorney General Keith Ellison said in a statement. "For too many Minnesotans, Frontier broke its promises."

In a statement, Frontier said it "is pleased to have this matter resolved."

Frontier, which also operates under the name Citizens Communications, is Minnesota's second-largest landline telephone provider with 90,000 customers, many in rural northeastern and southern parts of the state. Norwalk, Conn.-based Frontier also is a major internet provider.

The Minnesota Public Utilities Commission began looking into Frontier in 2018 after fielding a host of customer complaints. The PUC ordered an inquiry by the Minnesota Department of Commerce.

In January 2019, the Commerce Department issued a scathing report concluding that Frontier may have broken 35 laws and failed its Minnesota customers with shoddy phone and internet service, lax record-keeping and inadequate investment in its own network. Frontier has denied it broke any laws.

Last fall, the company and the Commerce Department came to a settlement that was approved by the PUC. It called for refunds for aggrieved customers and established a framework to deal with any future Frontier phone service problems and maintenance breakdowns.

That settlement covered phone service, not internet service, since the latter isn't in the PUC's regulatory purview. Frontier's settlement with the Attorney General's Office focused on broadband.

Under the agreement with the AG's office, Frontier is to "reform its sales and advertising practices" so that customers are better informed about internet speed. The company is also to ensure that customers' maximum internet speed is at least 90% of the top speed advertised in Frontier's service plans.

The settlement calls for Frontier to spend at least $10 million over four years to improve its internet network — money above and beyond the company's current investment commitments and any broadband-related government grants that the company may receive.

Under the agreement, Frontier will pay the $750,000 to the AG's Office, which could then distribute that money to Frontier's customers for "past harm."