Mental Harrasment at work place

I have joined my current company in place of one lady who was going on maternity leave. Everything was working fine for 6 months but after her maternity leaves got over she again joined in my team and after that my line Manager started treating me like an extra resource. Furthermore to target me they put me in Performance Improvement Plan for 2 Months, as per Performance Improvement policy they have to give me weekly feedback which never happened , rather after 15 days in PEP they started forcing me to put down my papers & also threaten me to give me my bad reviews to HR so that i will not get transfer in another team. The final review need to happen after 2 months, which they have taken after 3 month....till one months extra i was working not even knowing that the PEP is still going or not, and in this review both my mangers bring HR in discussion. I have kept all my points i front of HR...HR is giving me solution to take take 2 Month salary & leave the company...but this will not solve my problem as i shifted from another city...atleast i need better compensation. Also they intentionally gave poor rating of mine so that i didnt get my variable pay...its a huge financial loss for me...Please help with solution.