BOM Conversion issues with solutions in Oracle Apps r12

1)
Item CAR is a standard item.  Such items can only have Standard or ATO Standard items as components.  Please check these attributes for component TIER.
Solution:goto inventory-->items-->master items-->query with the "TIER"
goto order management tab,in this uncheck the check box of  pick components,assemblt to order  fileds.
now run import program,records will fetch from interface to base tables

2)
The item sequence number 5 you have entered for component TIER is not unique within the bill.
Solution: this will be data issue,go to bills of material -->bills-->bills
query for the PARENT COMPONENT of this child item(TIER)
After quering,next query child item under parent item,and see the item sequence number.in this you will find already number 5 is exist.
so,we can report it as date issue.