Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.Brazil’s National Civil Aviation Agency has suspended all flights operated by airline Avianca Brasil due to safety concerns, the AP reports.The flight ban was announced on Friday afternoon, but it was not immediately clear what the specific safety issues were that grounded the carrier’s planes. Avianca Brasil licenses its name from the Colombian airline Avianca, but it operates independently.Brazilian aviation authorities said that the airline must rebook or refund all of its passengers.The mass grounding is the latest blow for Avianca Brasil, which has had a rocky few months. In December, the airline filed for bankruptcy. Then, in April, the carrier nixed routes from Sao Paolo to New York, Miami and Santiago, Chile, and canceled more than 1,000 flights when it had to return 18 planes to leasing agencies, according to AP.