Flipkart — complaint about updating my old phone number with new phone number

I have created my flipkart account before some years with the phone number 7708527xxx and the mail id cn.[protected]@gmail.com. I have changed my phone number before 2 years and logged in the flipkart account with my gmail account. When I try to update my new phone number in the flipkart account, the otps are sent to both old and new phone numbers. I couldn't get the otp sent to old phone number as I changed the phone number. When I tried calling flipkart customer care from my new phone number, its not getting connected because its not registered with flipkart. I am using the same flipkart account till date and I want the same to be continued. Could anyone please help me to resolve this problem.