Hi Boris
Assuming you mean sage and purchase invoices then creditors control account - usually 2100. Also - go to Suppliers tab---> Reports ---> Aged creditors report.
If its sales - debtors control 1100. Customer tab ---> Reports ---> Aged debtors report.
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Joanne
Winner of Bookkeeper of the Year 2015, 2016 & 2017
Thoughts are my own/not to be regarded as official advice,which should be sought from a suitably qualified Accountant.
You should check out answers with reference to the legal position