Not committing to promise to waive installation fee?

Almost 2 months ago when I called to set up my internet service at my new apartment (I'm a new AT&T customer) I was promised that the $99 installation fee would be waived. However, it showed up on my first bill last month. I've since contacted customer service via online chat 3 different times inquiring about this, and every time I've been promised the charge will be removed from my account. But that $99 still shows up on my balance. Has anyone else had this problem? The "bill" is due by the 22nd and I don't want to get charged for not paying it on time when I shouldn't have to anyways.