Bile drain not decreasing after ERCP.

My father was diagnosed with Perforated Gall Bladder with Calculus with Right Subhepatic Abscess. Laparoscopic Cholecystectomy was performed with Drainage of Right Subhepatic Abscess and Repair of Bile Duct on 23rd Feb 2021. The bile drain was gradually decreasing from 100 ml to 5 ml for 1 month but from 28th Mar 2021 it again increased alarmingly and Bilirubin Test revealed Bile Leak. As suggested by gastrosurgeon, ERCP was performed and a plastic stent was implanted on 3rd Apr 2021. It has been more than 1.5 month after ERCP, but the bile drain amount is not getting reduced, instead it is increasing with each passing day. It is currently 200 ml in 24 hours. The stent was to be removed after 4weeks of ERCP. The date has passed but as the drain has not reduced, the stent could not be removed yet. What needs to be done in this situation? Why is the bile amount not decreasing? What is the normal time expected for the bile amount to get reduced/stopped after ERCP?