Why am I unable to tick 'Fully Paid' within the Share Register?

Within the Share Register a Share Type will become ‘Fully Paid’ where the ‘Total Payable’ per Transaction is equal to the ‘Total Paid’. The tick box provided on the Share Type Details screen is an automatic entry based on the above (hence why the field is greyed out). Users should select Edit | Share Register | Transactions [tab] | View, on each Transaction make sure these two fields ‘Total Payable/Paid’ agree. If not amend as required and re-check the ‘Fully Paid’ tick box within the Share Type screen. Note: Some Transactions may be present as a result of a Share Transfer. When entering a Share Transfer although no money is to change hands, the Share Type if previously ‘Fully Paid’ will need to remain so. Therefore if entering a Share Transfer the ‘Payable per share’ and ‘Total paid’ fields must be completed. If not the Share Type will not show ‘Fully Paid’ correctly. If a Share Transfer has already been created users will need to [View] the Transfer, select [Delete] and re-enter as above. If the problem persists please contact IRIS Support.