Termination of Employment: Understanding Your Rights
Termination of employment should be guided by company policy and the forms/documents you sign during the joining formalities or thereafter. Here, I am assuming that no communication was done at their end to inform you about the terms and conditions of termination. This is also not mentioned in your appointment letter or any other letter you signed, as per your explanation above.
If in your appointment letter or any other letter that you signed, it is mentioned that the employer can terminate the employee at any point in time without citing any reason, then they can make this decision. They are not wrong at this point because they are following their policy. This practice is being adopted by numerous companies nowadays. However, this is a wrong practice.
Now, coming to your queries, considering you didn't sign any such documents. If it is a verbal intimation, then don't worry and keep doing your work as you have been doing unless you receive any written intimation.
If the intimation is written, then send them an email in response to this termination letter asking about the reason for the same. If the reason is already mentioned in the letter, then tell them you were not informed about the terms and conditions of termination (in the case of this 5th attempt) and how they can terminate you without informing you of the rule and issuing a warning letter beforehand. They may try to demoralize you or put pressure on you so that you resign on your own, but be strong and ask for answers. Wait for the response, and then let me know. I will tell you what to do next.
Please remember, no employer can terminate an employee without issuing a warning letter/notice or a show-cause notice. Every employee should be given a chance to present their point for justification, provided the employee didn't sign any such documents as mentioned above.
For any further clarity on the same, please write back to me.
Regards