Likely that item already exists. See this thread

https://www.sagecity.com/us/sage300_erp/f/sage-300-financials-suite/98412/item-number-change-error

i saw the post, the item is not existing in the system. 

It likely is there - otherwise no error.
I would use SQL Management studio and search for that string in the entire database.
Find it, run a Sage dump, then remove offending records at your own risk.

Several tools exist to do a text search inside MS-SQL. If you don't have one up your sleeve, I use the store procedure created by this query:

Go halfway down the thread, to the code starting with the following, use that one.

IF OBJECT_ID('sp_KeywordSearch', 'P') IS NOT NULL
    DROP PROC sp_KeywordSearch
GO

https://stackoverflow.com/questions/15757263/find-a-string-by-searching-all-tables-in-sql-server

It likely is there - otherwise no error.
I would use SQL Management studio and search for that string in the entire database.
Find it, run a Sage dump, then remove offending records at your own risk.

Several tools exist to do a text search inside MS-SQL. If you don't have one up your sleeve, I use the store procedure created by this query:

Go halfway down the thread, to the code starting with the following, use that one.

IF OBJECT_ID('sp_KeywordSearch', 'P') IS NOT NULL
    DROP PROC sp_KeywordSearch
GO

https://stackoverflow.com/questions/15757263/find-a-string-by-searching-all-tables-in-sql-server