Auto Repair Business Forms

Collected sales tax in PA, what form do I submit to PA Dept of Revenue?
I just started an auto repair business and must send in my sales tax. I sent PA Dept of Revenue two emails, both no reply (imagine that, our tax dollars at work effectively once again). It is due tomorrow. What form? Help! Thanks.
BTW their website is not helpful about which form to submit with sales tax, I work 7 days a week long hours, don’t want to sift through FAQs or spend time on the phone, I just need to know exactly which form I need to file. Thanks.
You submit the sales tax return online or by phone to an automated system, and mail in a check or have it direct debited. They dropped allowing the paper form filing about a year or two ago. I have found the telephone system easier to use than the online system.
See http://www.doreservices.state.pa.us/BusinessTax/TeleFileST.htm
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