Minnesota U.S. Sen. Tina Smith said she’s talked with postal leaders about the problem.

“It’s concerning because when they responded to our first question about the people not getting paid, they said this is something they had fixed and it wouldn’t happen again. And then — lo and behold, barely a month later — we have the same problem again with fewer people, but with similar challenges,” Smith said.

A spokesperson for Smith says letter carriers who missed paychecks in September were “made whole” in the next paycheck they received. For those who missed paychecks in November, it’s not known if they’ve been paid the wages they are due yet.

“It’s very frustrating and quite concerning that they just don’t seem to be able to get their act together,” Smith said. “This is more than just an inconvenience for folks to not get their paycheck. I think our communications with them has been very stern.”

There have also been complaints of slow mail delivery in rural America. Earlier this week, MPR News reported on workload concerns and delivery delays in Bemidji.

One postal worker told MPR News that his job — especially this time of the year — is all-consuming. He often works more than 14 hours a day.

The Postal Service declined an MPR News interview request to talk about mail carrier allegations for that story. Instead, it provided a written statement saying it is “strongly positioned” to handle the onslaught of holiday package and mail deliveries.