The most probable reason is the change in your mobility plan. Below are the main reasons for this change:
Your corporate mobile number converted to personal number
Your personal mobile number converted to corporate number
Pre-paid number converted to Post-paid or vice versa.
If you had verified your email id in JioCloud earlier, you can login to your original account using that verified email id and OTP. If you are still not able to access your account then please contact JioCloud customer care on email@example.com mentioning your mobile number and we shall get it solved for you.