Ok, this is the symptom that people who wear flip flops or sandals have.
That is flip flops or sandals have too much friction on the floor.
So when a person in flip flops etc walks, they may fall or nearly fall because the flip flops have strong friction on the floor & may cause a force that stops that person moving forward, but since the person is walking so he has a momentum of moving forward.
These 2 opposite forces may make him fall down.
trip [intransitive] to catch your foot on something and fall or almost fall
She tripped and fell.
trip over/on something Someone will trip over that cable.
(figurative) I was tripping over my words in my excitement to tell them the news.
trip over/up Be careful you don't trip up on the step.
So, may I say?
My toddler tripped over the floor in her sandals
People often trip over a cable or a step, I am not sure if people do trip over the floor?
We may say "trip on the floor" but that may cause confusing because people may think "trip over a cable on the floor"