Sandisk Cruzer Ultra Flair 64 GB has only 2.80 GB


I own a USB 3.0 Flash drive Sandisk Cruzer Ultra of 64 GB which is at 2.80 GB now of capacity. I bought it on July 2019 and worked very well. I used it a very few times and now it seems its capacity got reduced for a reason I don’t understand.

I formated it on FAT32, and I tried other formats too, and if I use it on USB 2.0 or 3.0 ports I still meet this problem.  

Need help please ! :( 

Thank you to have read my message. 

The drive has been partitioned by some app and Windows can only see/access the 1st partition on removable drives.

Look at the USB drive in Disk Management.