Simple Fund 360 has built-in safeguards to uphold the data integrity. SF360 may lock a transaction to preserve the correct capital gains calculation.
If you are attempting to edit a transaction and it is locked, check that the investment account has no future dated transactions.
If you need to adjust the locked transaction you will have to reallocate any future dated transactions to the investment. Please refer to the following FAQ for more information.
https://360help.com.au/pages/viewpage.action?pageId=23629979
Further Tip : Check out the new “CGT Register” excel export in the “Transaction” menu.
From the CGT Register page , input the relevant date (Contract Date) and select Download Excel.
Find the original transaction you want to unlock in the sheet
Then scan right to the “Cost Base Link” column
This "Cost Base Link " will assist you in tracking which CGT events are locking the original purchase and subsequent CGT events.
Look for the same Link Number in the sheet to locate the locking events
You then need to remove/reprocess those events only
More info here
https://360help.com.au/display/SF360GS/CGT+Register