SQL Developer Query returning blank output - sql

Question

I want to only see all records that are in position "substr(B.GLDEBITACCT,24,8)" from the string below
'FDN-XXXXXX-XXXXXXX-XXX-XXTXXXXX-0000-0000'
So in my query displayed below, I chose to specifically pull in all records by the letter 'T' so I wrote the syntax as AND SUBSTR(M.GLDEBITACCT,24,8) = 'T'. Now this is giving me a blank output. Can someone help me decipher what I am not doing right here? I hope my question is succinct enough.
SELECT
SUBSTR(M.GLDEBITACCT,24,8) as PROJECT,
G.COMPTEXT AS PROJECT_NAME,
' ' PROJECT_LEADER,
TO_CHAR(W.EX2DERNUM) AS DERNUM,
' ' AS DERLINENUM,
' ' AS REQUESTNUM,
M.REFWO AS WONUM,
W.PARENT AS PARENT_WONUM,
' ' AS PRNUM,
' ' AS PRLINENUM,
' ' AS PR_STATUS,
TO_CHAR(M.PONUM) AS PO_NUMBER,
TO_CHAR(M.POLINENUM) AS POLINE_NUMBER,
' ' AS PO_STATUS,
' ' AS PO_REVISIONNUM,
' ' AS PO_VENDOR_NUM,
' ' AS VENDOR,
M.ITEMNUM,
M.DESCRIPTION,
I.ISSUEUNIT AS UOM,
TO_CHAR(M.QTYREQUESTED) AS WO_QTY_REQ,
TO_CHAR(M.QUANTITY) AS WO_QTY_RECEIVED,
TO_CHAR(M.UNITCOST) AS WO_UNITCOST,
TO_CHAR(M.LINECOST) AS WO_LINECOST,
M.ISSUETYPE,
TO_CHAR(M.ACTUALDATE) AS ISSUEDATE,
W.STATUS AS WONUM_STATUS,
' ' AS PR_QTY_REQ,
' ' AS PO_QTY_REQ,
' ' AS ACTUAL_QTY_RECEIVED,
' ' AS PO_QTY_RECEIVED,
' ' AS PO_QTY_OPEN,
' ' AS PO_UNITCOST,
' ' AS PO_LINECOST,
' ' AS SHIPTO,
' ' AS DROP_SHIP,
' ' AS ENTERDATE,
' ' AS REQDELIVERYDATE,
' ' AS VENDELIVERYDATE,
' ' AS STATUSDATE,
' ' AS RECEIPTDATE,
' ' AS DIRECT_CHARGE,
' ' AS VENDROR_COMMENT
FROM MSCRADS.MATUSETRANS M
LEFT OUTER JOIN
MXRADS.WORKORDER W ON
M.REFWO = W.WONUM
LEFT OUTER JOIN
MXRADS.ITEM I ON
M.ITEMNUM = I.ITEMNUM
LEFT OUTER JOIN
MXRADS.VW_GLCOMPONENTS G
ON SUBSTR(M.GLDEBITACCT,24,8) = G.COMPVALUE
WHERE M.ISSUETYPE IN ('ISSUE','RETURN')
AND M.SITEID = 'FDN'
AND M.PONUM IS NULL
AND M.ACTUALDATE >= TO_DATE('2014-05-26','YYYY-MM-DD')
AND SUBSTR(M.GLDEBITACCT,24,8) = 'T'
ORDER BY 1