"After a thorough medical evaluation, it has been confirmed that Janet’s symptoms are being caused by a rare form of migraine called vestibular migraine or migraine-associated vertigo for which she is currently receiving treatment," read a statement released by Jackson's camp and obtained by E! News.
"Janet wanted very much to resume her tour so as not to disappoint her fans, but she continued to suffer from vertigo and could not perform," her manager, Kenneth Crear, said.
"She's a world-class entertainer and needs to be at the top of her game to give her fans the show they expect. She's feeling much better and is ready to hit the road again to finish the tour."
I was researching that type of migraine she was suffering from and it explains why she cancelled all of those shows.