Merge General Ledger Accounts - Import Error - A subquery has returned not exactly one row

Merge General Ledger Accounts - Error:
Munis (glacctmr)
Unknown error on fetch. -284 [ISAM -1]
A subquery has returned not exactly one row
System log Id: #
Message: Fetch 2062

• Account Merge
• Project Code
• Use Project Accounting
• Error Message

• General Ledger Settings Segment Sizes tab Segment Order Settings is missing Project in the order of account entry
• When "Use project accounting" is selected in GL Settings and Project Codes exist tied to GL accounts
• Short Account has Project Code, Long Account does not and results in duplication of (segment 1-8+object) which Munis cannot tell apart

1. Update Order of Account Entry in General Ledger Settings to include Project Code
2. Contact Munis Financial Support to run a utility to rebuild long accounts according to order of account entry
3. Try Account Merge Import again

Workaround if site does not want to update GL Setting for order of account entry:  Manual merge and bypassing import feature