how to change the default write disk back to Phone storage from SD card on Android 6

[Android Central Question]

I added an SD card class 10 to my phone and when formatting it in order to choose it as default write disk, a warning message said that this card is too slow and may affect apps performance. Since I wanted to move only my photos and apps that are not important for performance I went ahead formatted the card and move all photos and some apps on it. I also chose it as default write disk assuming this as a requirement for saving photos on the SD card when taking them.
Later I searched Google for "sd card class 10 too slow android" and some results suggested that the card might be defective.
I decided to go to the store and ask for replacing the card. I tried to move back my photos and apps from the SD card to the phone storage.
I moved the apps back but I can't find a way to move the photos back. I also can't find a way to set the phone storage as default write disk. In the settings there is only an option to set the SD card as a default write disk and one radial button next to it. Pressing that button keeps it always on.

I guess a work around would be to copy the photos to computer and move out or format the sd card but I want to find out if there is a better way.

I will greatly appreciate your help with this

 

[RossSmalls]

I posted the original question and this is a follow up.
In the storage settings I chose the Phone storage and chose Migrate data from the only option in the menu. This showed a message which I understood as to move the data from the SD card to the phone storage. I chose it and a progress bar showed processing. When finished a notification came that some data was not moved. Then I checked the SD card storage and it shows that there is nothing there. it showed two items: Apps 0.00 B and Cashed data 0.00 B. but on top it said 1.12 GB used of 28.50 GB. Then I looked for my photos in the Phone and there were nowhere to be found. Did i lost them forever?
Please help!

 

[RossSmalls]

Another follow up.
Restarted the phone and managed to access the photos. They were still on the SD card. Looks like the 'Migrate Data' didn't work. Maybe because now there is not enough space to move the data back after many apps on the phone storage updated when they saw available space after I moved the photos to the SD card. I guess this reduced the free space on the Phone storage and I can't move the photos back.
I will greatly appreciate any input