wireless contract created with error's

You received a customer service summary which named your plan and indicated you had Next Up.

Since that's not what you want, log into your account and change to the plan you want and remove Next Up. 

The bill you received is not "estimated." It is the actual amount due. Not only is it higher because of the one-time fees and lack of promo credits, it also includes more than one month of service. You should pay it in full by the due date. 

You will get a prorated credit on the next bill for the difference between the Extra and Starter plans from the date of change to the end of the billing cycle. 

If it's worth your time, you can call and request credits for the difference in prices up until today. Like you said though, it's not a big dollar amount, so you'd have to weigh the time spend vs. the money received. I suggest making the changes online first, though, so you know those are done correctly and you'd only be asking for a bill credit. 

@MicCheck Pretty sure that what the OP received in the mail was the projected bill also known as the customer service summary, not the actual bill. As we all know, the projected bill is infamously wrong. Since you must sign up for both autopay and paperless billing to get the advertised price, no bill should be mailed but I’m pretty sure that customer service summary does still get mailed. The last time I did a plan change, they mailed the customer service summary even though I already had autopay and paperless billing.

@sandblaster I thought about that, but since he said it was due in 3 weeks, I assumed it was a bill. 

@donaldjsr If it is the Customer Service Summary, then you just need to make the changes yourself online. 

Thanks to all who responded to my request/problem.  Your responses were greatly appreciated.

I am retired and on a fixed income, with checks coming on the first and middle of the month.  My first check takes care of medications, groceries, and utility bills.  The second check pays for other expenses like my phone bill and any medical bills acquired during the month.  I had always paid my phone bill with the check I received on the closest Wednesday to the 15th, and ATT cooperated with that request.  I had to purchase a new phone and to get a discount, I had to sign up for autopay.  I asked that my previous arrangement be honored and allow my bill to come in the middle of the month so I would know my budget would still work.  I got my email stating that the autopay would take place on the 31st of March.  Now I'm in a bind because the amount of money might not be available in my account.  I've talked to ATT again and was told there was nothing they could do and that the bill would have to be paid on time or I would lose the discount I was given for going autopay.  It's tough growing old and having other people decide how to run your life.

The due date didn't change because of any of the other changes you made. It was probably always the end of the month and you just paid early. 

In any case, if the funds are available on the 15th they should still be available on the 31th unless you decide to spend them elsewhere. 

Your best bet might be to pay with a credit card. Then you can pay the credit card balance when it's most convenient for you but still get the discount for autopay.

@pogo865 As noted, your due date should not have changed from ordering a phone or signing up for autopay, however autopay is scheduled two days before the due date unless using a credit card, in which case autopay would be 15 days before the due date. If you are using a credit card for autopay, then the autopay date shouldn’t matter but if you used a debit card, it may have incorrectly been identified as a credit card and autopay is scheduled too early. If that’s the case, changing your autopay to your bank account might be the solution. Otherwise, the only way to change the autopay date is to request a change to your bill cycle dates.