Worst service ever

The service of this Network is so bad, they should not even been given a star. They take 1st place for the worst service I have ever received. Upgraded my wifes contract in May 2020 and added a 2GB booster bundle. We are 3 months later, being billed for it but not receiving the 2GB booster bundle. Have been to the store several times, they escalate the qeury but that does not get resolved. Apparently it is loaded onto the line but we do not receive it. What more can a person do?