Time Warner Cable is working to figure out what caused three interruptions today in its digital phone service.

Time Warner spokesman Andrew Russell didn’t know how many customers were affected by the outages. He said the first occurred this morning and lasted an hour, the second was late in the morning and lasted 25 minutes, and a third lasted 10 minutes around 1 p.m.

“It affected commercial and residential customers across our footprint,” Russell said. He added that 911 calls weren’t affected.

Some businesses, including Longfellow Books in Portland, reported that their credit card machines were down due to the interruptions.

Chris Bowe, a co-owner of the bookstore, said he used a portable credit card machine during the outage.

“We did go old-school for a while,” he said.

Although customers were still able to pay with credit cards, Bowe said, no one could call in orders.

“It’s hard to say what the effect is,” he said. “I don’t know how many phone calls I didn’t get.”

Russell said those affected should contact Time Warner’s customer care center.

Bowe said he hopes to get reimbursed by the cable company in some way for the time he was without phone service.

“They should at least buy us some ice cream or something,” he said.