Changes in notice period, annual leave and appraisal with a lock period

I'm working in an IT company. Our management changes the company policies last month. I have not acknowledge the mail yet. They reduced my annual paid leaves and changed my notice period from 60-90 days to 90 days. Also in my appraisal letter they have mentioned that the appraisal is applicable from 1st May but I have to serve locking period of 6 months from 15 June excluding notice period. They have not informed me about this locking period while discussing increment amount. Please check below not added in appraisal letter. And also they changed my role in appraisal letter. In appointment letter they mentioned as software developer and now they mentioned in as .net developer **Note: This Appraisal with the newly revised monthly salary will be valid and hold true, subject to your continuity of current role, responsibilities and service as an employee with us for a minimum period of 6 months from June 15th, 2021, excluding the notice period Please help me with this. Is this legal.