2631167 - Unique Index key activation issue at phase MAIN_NEWBAS/PARCONV_UPG_DS during system Upgrade via SAP SUM tool

During upgrade, SUM ran into below error at phase MAIN_NEWBAS/PARCONV_UPG_DS

Checks after phase MAIN_NEWBAS/PARCONV_UPG_DS were negative!
Last error code set:
1 TP processes failed - check PARCONV.ELG

ERROR:
Trouble Ticket Generation
A trouble ticket and an archive with all relevant log files have been generated.
Trouble ticket: "K:\usr\sap\<SID>\SUM\abap\log\SAPup_troubleticket.log"
Log archive: "K:\usr\sap\<SID>\SUM\abap\log\SAPup_troubleticket_logs.sar"

[SAPup.log]

CURRENTPHASE MAIN_NEWBAS/PARCONV_UPG_DS
...started at 20180130135835
# Using phase log file 'PARCONV.LOG'.
...begin processing at 20180130135836
...finished at 20180130135912 with status FAILED.
# Error message set: '1 TP processes failed - check PARCONV.ELG'

[PARCONV.ELG]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Check TP process and RETURN CODE in PD990130_PARCONV_UPG_DS.<SID>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3 ETP000 CREATE UNIQUE INDEX "SMSCMAID~A01" ON "SMSCMAID"
3 ETP000 ("MANDT",
3 ETP000 "SCHEDULERID")
3 ETP000 
2WETP000 13:58:58: Retcode 1: error in DDL statement for "SMSCMAID " - repeat
2EETP345 13:59:10: Retcode 1: SQL-error "349-cannot CREATE UNIQUE INDEX; duplicate key found: [5] 
2EETP345 Several documents with the same ID exist in the index;SAPABAP1:SMSCMAID.$uc_SMSCMAID~A01$ 
2EETP345 content not unique, cannot define unique constraint. rowCount != distinctCount " in DDL st
2EETP345 atement for "SMSCMAID "
2 ETP000 --------------- DB-ROLLBACK() ---------------
2EETP334 13:59:10: error in DDL, nametab for "SMSCMAID" not activated
1 ETP111 exit code : "8"

• Software Update Manager (SUM) 1.0
• Software Update Manager (SUM) 2.0

SMSCMAID table, unique key, index, validation, CA-GTF-SCM, MAIN_NEWBAS/PARCONV_UPG_DS, PARCONV.ELG, SUM upgrade, Software Update Manager, DDIC, Downtime, DDL statement, tp process, duplicate key, SQL-error, not activated , KBA , BC-UPG-TLS-TLA , Upgrade tools for ABAP , Problem