San Jose’s customer care phone lines were tied up all day today as confused residents tried to find out why they received letters for not paying their garbage service fees when in fact they had.

The city mailed out about 33,000 such letters on June 26 in an effort to collect delinquent payments before a switch in billing practices. Starting on Thursday, waste pickup and recycling fees will be accrued onto property tax bills instead of charged through bimonthly bills.

The letters were supposed to be sent to property owners who hadn’t paid their bills by June 22.

They warn that failure to pay outstanding garbage bills will result in a $6 surcharge on their tax bills and note that a public hearing on protests has been scheduled for July 9.

However, many residents who had paid their bills using an auto-pay feature got the letters, too.

Willow Glen resident Mary Sidlauskas said she got the letter and interpreted it as a threat to place a lien on her property. Other residents flooded call centers with similar concerns.

“I am on auto pay and the money was taken out of my account on June 24,” Sidlauskas said. “I called the city and they said that the letters had gone out in error and that they were receiving a lot of calls about them.”

Indeed, many frustrated property owners spent hours on the phone trying to get through to San Jose’s Customer Contact Center, leading the Environmental Services Department to send a social media blast directing customers to email the department rather than call.

“Clearly it’s a mistake, but it’s frustrating to not be able to get a hold of anyone,” said resident Kate Leehane, who also received the letter despite having paid her bill.

Some people who pay bills online also got tangled up in the system because they paid on or right after June 22, according to Ed Bautista, spokesman for the Environmental Services Department.

“They may have paid but it wasn’t captured yet,” he said, adding that anyone who used online banking or auto-pay systems to pay after June 22 may get the letter. If residents know they paid on time, they should disregard the letter, he added.

Beginning on Thursday, residents will no longer receive a garbage and recycling bill.

Residents are asked to email customerservice@sanjoseca.gov with any questions regarding the new billing system.