TLC’s T-Boz is recovering from an allergic reaction that has forced the group to reschedule shows on their Celebration of CrazySexyCool Tour.

“TLC has rescheduled the Saturday, October 2nd show at the Smart Financial Center in Houston, TX to Monday, October 4th,” read a notice posted on TLC’s Twitter account on Saturday.

The note explained the circumstances: “Due to extreme cigarette and recreational smoke being present backstage at a previous show, T-Boz suffered an allergic reaction. The group has always enforced a strict no smoking policy at their shows in an effort to prevent any health related issues for the group and/or crew.”

The venue announced on Twitter that “all previously purchased tickets will be honored for the new date.”

Later Saturday night, TLC announced a second show had been postponed: “TLC has rescheduled the Sunday, October 3rd show at the Pavilion at Toyota Music in Irving, TX to Tuesday, October 5th. We are so excited to see all our TLC fans there!!!”

T-Boz (Tionne Watkins) and Chilli (Rozonda Thomas) have been on the road with Bone Thugs-N-Harmony since early September.

The trek comes nearly 27 years after the release of their classic 1994 album CrazySexyCool, which peaked at No. 3 on the Billboard 200 albums chart and featured four Billboard Hot 100 top 5 hits, including the No. 1s “Creep” and “Waterfalls.” (TLC’s third member, Lisa “Left Eye” Lopes, died at age 30 in a car crash in 2002.)

“We love what we do until this day,” Chilli told Billboard in an interview ahead of the tour.

See the tour dates on TLC’s website, and read their updates below.