Update locked interactive PDF - XFA form

This month list finished on September 2019, I need to add every month from October 2019 up to December 2023. Every month has own coefeicint number "Tarif" and calculate data on the background, Nombre de litres x Tarif = Montant a recuperer. Also the dates of "Periode du 01/11/2018 jusque au 30/11/2018 changes every month. The PDF is probably locked. Check Clipboard04.jpg first. I would like to work with the project now and finish with updated PDF in one-two hour.