How to format a USB drive and increase its available size? I have a 32 GB USB flash drive which is currently formatted to 261 MB:

How can I reformat/erase that USB drive so that I access all 30.75 GB of it?
Disk utility won't let me change the size of the partition to 30.75 GB.
Update 1: I erased the drive. At the end, there was this dialog box.

Update 2: I took the path of least resistance and changed the size of the drive to 30 GB on a Windows machine (discmgmt.dsc utility).
If you can you might trying erasing the disk and then reformat it. You will, of course, lose everything written to disk. If you want to keep what's on the disk you could copy it you main drive. Disk utility allows you to erase the disk and then reformat it.
After opening Disk Utility go to the Edit menu and at the top of the panal you'll see option to erase, partition, and other commands.