Guess they really don’t ever stop working for us? Verizon Wireless announced Sunday that it will refund up to $90 million to customers who have been overcharged for data usage on their cellphones. Hundreds of the company’s subscribers had complained to the Federal Communications Commission about the incorrect charges, many of which resulted from Internet software built into customers’ phones that was inadvertently triggered. About 15 million people will receive refunds between $2 and $6 on their phone bills for October and November; previous customers will receive checks. “[W]e always want to do the right thing for our customers,” a Verizon spokeswoman said.