Problems with Samsung’s replacement Galaxy Note 7 smartphone are prompting some wireless carriers to take back the devices for exchanges or refunds.

The replacement Note 7, available for the past few weeks, was supposed to correct a flaw that had led to exploding batteries in the original model. But this week, a replacement Note 7 apparently caught fire on a Southwest airplane in Louisville, KY.
That prompted a new round of handwringing and exchange offers.

Sprint s said it is working with Samsung to determine whether there are any problems with the replacement devices. In the meantime, customers with a replacement Note 7 can exchange it for any other device at a Sprint retail store.

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AT&T t said customers with a replacement Note 7 can exchange them for another device.

T-Mobile tmus said customers who bought a new Note 7 since sales resumed on October 5 or have already turned in an original Note 7 for a replacement model would have 14 days to get a full refund or exchange the phone for another device.

Verizon Communications vz said it would offer customers with a replacement Note 7 an opportunity to it exchange for another smartphone starting on Saturday. Customers should make the exchange at the place where they made their original purchase or, in the case of Verizon online purchases, at a Verizon store. 

The Note 7, which has a 5.7-inch screen and comes with a stylus, was selling well for Samsung in August. But owners started encountering problems as the device overheated and, in dozens of cases, caught fire because of a battery-related flaw. Last month, the Consumer Product Safety Commission issued a recall for some 1 million Note 7 phones sold in the United States.

(Update: This story was updated at 1:15 p.m. on October 7 with additional comments from T-Mobile and at 2 p.m. with Verizon’s comment.)