Termination with one month notice

I was working as a PGT (Chemistry) in a recognized and CBSE affiliated The Jain International School on date 18th July 2018 after fulfilling all required processes i. e., demo class and personal interview by the principal. Keeping in mind the goodwill of this school, I have resigned from my previous school where I was working for last 3 years and accepted the offer letter of this school. As per the offer letter, I was offered appointment of 1 year on probation basis. After probation period I continued in this school as per my performance in the previous academic year meanwhile I received best teacher award but I have not received any official letter (appointment letter of permanentship ) or confirmation of my service nor any kind of cognizance which shows the authenticity of the employees. In-spite of this I am surprised to receive a letter of termination from management during this lockdown period. As such giving 1 month notice without citing specific reasons is only based on the breaches of the conditions mentioned in the offer of appointment. During my termination I have been deputed for the CBSE Board Examination evaluation from this school.