Am I eligible for unemployment

I was recently told that I needed to improve my performance at my job. I was give 3 weeks unpaid leave to sort out my personal issues. After the 3 weeks I was informed that nature of my work had been altered significantly from my original hiring expectations. I was told that in order to stay in the current position I would have to acquire new skills which they would help with and send me to class for. Basically this mean I am starting from scratch and loose all my seniority and now I would become the junior most member of the group. I am not willing to do so. The company gave me 5 weeks to find a new job either within the company or outside. I recently talked to HR to find out if I could not find a new job and was let go, if I could collect unemployment. HR informed me as this is coded as a voluntary resignation and as so I am not eligible for unemployment. I am sort of confused why is this considered voluntary resignation as the company changed the nature of my job significantly. What are my right here? Will I be able to collect unemployment? Please advise. Thank you.