Airtel — active data packs never worked.

I have a prepaid plan of daily 1.5gb of data on my mobile. But due to work from home policy 1.5gb is not sufficient and have recharged using ₹98/- and ₹251/- data packs which comes with data validity of existing prepaid base plan which is 365 days. But as soon as my daily limit completes my speed reduces to 64kbps even i have active data packs with 12gb and 50gb. They are never applied/available to use. Despite calling customer care executive with effort not less than 1hr always my issue never resolved. Kindly address this, as this is a serious fraud and cheating by making customers pay for additional data packs and never get benefits of the plans activated.