Several students have had their phones shut off or their personal access codes (PACs) deactivated in the past week because of unpaid bills, but some claim the billing system used by the Harvard Student Telephone Office is at fault.

"In the ballpark of 150 lines and 300 PAC [codes]," Jack Wise, manager of the Harvard Student Telephone Office, said yesterday when asked about the number of students affected.

Wise said his office usually shuts down telephone service "60 days from the date of [an overdue] billing."

But many students who lost service said they feel the 60-day period is not adequate because they do not always receive their monthly bills.

Students say that many of the December bills were late. And bills that went unpaid in December could be forcing the shut down of lines and PAC codes now.

"The December [bill] arrived in February along with the January," said Caroline A.Butler '97.

Students also complain that the billing system is confusing. Nasreen B. Bulos '97 said the telephone office often does not credit payments to her account completely.

"I really can't understand how much I owe them [because] the bills are so screwed up," Bulos said.

Bulos said she had been paying her bills, but the telephone office was tacking on debt as if she had not.

"The first [bill] was for $200, the second for $500 and the third was for $900," she said.

Wise acknowledged that the December bills had been late.

"We've tried to check into that, but it's a problem since we're always a month behind," Wise said.

Wise said students who have not received bills should contact the telephone office to rectify the problem.

"If someone has not received a bill they should notify our office," he said. "We'll flag that account so you won't be affected."

This year, Wise said the telephone office has instituted a new policy of sending students letters of notificationtelling them when service is about to be cut off.Last year the bill alone was considerednotification.

But Wise said the number of students whohaven't paid is small compared with the totalnumber of 8500 who have phone service.

"The vast majority of students pay theirbills," Wise said