If that is a copy/paste of your exact code then you just need to correct it, spaces here and there. Plus remove the redundant where clause. Maybe:
SELECT C001 BAC_CODE, C002 UPSC
FROM APEX_COLLECTIONS CA
WHERE COLLECTION_NAME = 'UPLOADED_EXCEL'
SELECT BAC_CODE, UPSC
FROM UPLOADED_DID_LIST UPLD
Thank you for this! It was indeed a syntax-error!