Installation analysis of hdpe pipeline

Hello sir/madam

A 3.5 km HDPE pipeline of 1000mm diameter and 65mm thickness is being modeled and it is towed by the help of 2 barges supporting the pipe at its end.ROD class is used to define the pipe, and at some specific location along the length of pipe, the pipe is wrapped with a stud link chain of weight 22kg/m. Now in order to convert the positive buoyancy of pipe to negative the flood yes option is being used.

But there is no effect of the FLOOD YES option and the solution is not converging. Please give the required solution to the problem.