Internal storage is damaged, I don't know what to do?

I'm stuck in a screen that says:

"Internal storage is damaged and is now unavailable. Please choose one of the following options:

- restore factory settings

- restart phone"

If I select restore, it doesn't do anything. If I choose restart, It will just restart and go back to that same screen.

I have tried bringing it to the service centre of huawei, but they say it might be the board. And since this is already out of warranty, replacing the board will cost me a lot so they just told me to buy a new phone. But this phone is very important to me, so does anyone know how much is a board for this model? Thanks