Airtel — Data pack with a letter expiry getting consumed instead of the pack that will expire today

This is not the first time I have noticed this. I recharged my mobile today for the next 84 days with 6GB data. I already have a 4GB data pack. The validity of the packs after recharge shows the 4GB expiring today, and the 6+ GB expiring on 17th Oct 2023. But when I am using data the data is getting consumed from the pack that will expire on 17th Oct 2023, and not the one that will expire today by 23:59 Hrs. This is a cheating by Airtel. I am trying to raise the issue from the App but there is no way they are registering the complaint as it is asking which location, which OTT and all that. How does the data consumption balance have anything to do with Basement or 9th floor. I have tried to login a complaint but they say the complaint number will be send by SMS but I do not see any number received. And from past experience it will never come