Confused grandma

One time me and Krystal went to the toilets. A man was standing outside the girls toilets. He said to us "Could you go in and check on my mum? Shes been in there a while and she's pretty deaf."
"Sure." We walk in. There's only two toilets and one of them is engaged.
"What do we do?" Krystal looked at me and then softly knocked on the door, "Are you okay in there?"
"Oh, yes..I'm just trying to figure out how to unlock the door," a grandma's voice came sailing out.
"Oh," we tried to explain how to do it and finally after a while she got it and walked out saying "Thank you very much; thank you". By that time Krystal had gone to the other toilet. The grandma was still looking at me saying thank you as she went straight for the other toilet door, thinking it was the way out.
"Oh this is the way out," I opened the exit door which then leads to another door.
"Oh, thank you thank you," the grandma walked out and then started feeling around the brick walls for the other door. I directed her sideways, "It's here."
She turned around to thank me profusely once again and said, "How could I be so silly?" just as she started walking back into the bathroom because she was so confused with directions!