SD Card "Failed to change directory"

Hello everyone, new here!
I have an issue when I try to access the SD card on my two Organelles.
Both of them have new 3.1 system, the first one came with it preinstalled and I didn’t change anything in it.
The second one came with 2.something system and I updated the system to 3.1.
The message I get when trying to access the SD card with the X system is

Failed to change directory “/sdcard” (No such file or directory)

but the rest of the system works fine, Im’ using both Organelle for sounddesign and I have no other issue at all.
Both of them seem properly powered (I’m using the power supplies that came with them).
I also searched the forum, but didn’t find any Topic on this issue, if I missed it, sorry for openening a new redunt thread.
Any hint on what may be the cause?

Thanks in advance for any help!

It sounds like the storage partition on the SD card does not exist yet. This is to be expected if you upgraded from OS2.x to OS3.1. The OS upgrade does not add the partition.

What size is your SD card? If it 8GB or larger, you can do either of the following:

or

If it is a 4GB card, there is no space for a partition so you will have to get a larger card.

Thanks a lot for the fast response!
One of the SD is an 8GB, so I’ll try the solutions you suggested.
the other one is 4GB, so tomorrow I’ll do some shopping!

Thanks again for your help.