Run the command below in Terminal and paste the output up here so we can work through this with you.
If you have not already, do a full backup because we will likely end up erasing your drive here.
Right. Firstly I backed up everything. Secondly I formatted everything. I booted from a install USB and I still cannot resize. I will try and post it through the apple support safari bit
----------
CoreStorage logical volume groups (1 found)
|
+-- Logical Volume Group 238A24D8-4691-4F3E-8214-6C6077ECE094
=========================================================
Name: MacintoshHD
Status: Online
Size: 816256983040 B (816.3 GB)
Free Space: 65536 B (65.5 KB)
|
+-< Physical Volume A93EAA50-905D-431B-A91D-73C35FD6A298
| ----------------------------------------------------
| Index: 0
| Disk: disk0s2
| Status: Online
| Size: 127691702272 B (127.7 GB)
|
+-< Physical Volume AB8DDDF7-DE03-4D32-AFDE-CCA1006EB93A
| ----------------------------------------------------
| Index: 1
| Disk: disk1s2
| Status: Online
| Size: 688565280768 B (688.6 GB)
|
+-> Logical Volume Family 6FFEE567-124C-456F-A103-6E44CB90785B
----------------------------------------------------------
Encryption Status: Unlocked
Encryption Type: None
Conversion Status: NoConversion
Conversion Direction: -none-
Has Encrypted Extents: No
Fully Secure: No
Passphrase Required: No
|
+-> Logical Volume ACEE7C82-5769-4009-9F23-DD7A8014A0C1
---------------------------------------------------
Disk: disk3
Status: Online
Size (Total): 810364960768 B (810.4 GB)
Conversion Progress: -none-
Revertible: No
LV Name: Macintosh HD
Volume Name: Macintosh HD
Content Hint: Apple_HFS