Work Experience letter but no contact details!! Please Help

Hi everyone, my company gave me an experience letter with roles & responsibilities but there is no contact detail on the letter (Phone number or email-address). Now I went back and asked them to add the phone number & email address of the HR on the letter but they refused to do so.

BTW I asked the contact details of the HR who provided the letter, Instead should I have asked for company phone number and email? (Not sure they will agree to it anyways)

This is all in their ex employees portal, its not in an email. what do you all think my next step should be?

Actual work ex letter:

Response from Company:

Note: I have a few letters from 2018 when I left the company that does have contact information of HR but I am not sure if they are still working there or not.

Previous letters:

This was about a week before I actually left the company so I am not sure this is of any help or not!

EDIT: Masked HR’s name & Phone number

Well my post got approved after 15-18 days! But any replies are welcome.