Taking on the big guys!

In my line of work we deal with out sourced companies to provide payroll processing. I have been dealing with one of the big guys for several years. I left one big fish for the other. Can I tell you this has been drama since the very beginning. From the initial conversion to this latest bit of fun. So the beginning of January we were billed several thousand dollars supposedly for services provided in December.  I looked in to this briefly and quickly determined there was some type of error. I had one of my staff members call and they spoke to some one who assured them they had checked and this was a new fee, and not a duplication of charges.  I knew this could not be accurate, but had to table it for the moment.  As luck would have it I was contacted by a representative of the company...of course his interest was to sell me something new. I told him look...you want an appointment with me, get to the bottom of this issue and I will meet with you.  5 days later, he still had no answers.  So today, after he was still feeding me the I am not making any headway line, I made my own phone calls only to once again get transferred to a manager I have dealt with before. Rule number 1, when dealing with sticky issues...always ask for the bosses boss. And make sure the guy on the phone getting you there understands that you know how the system works.  At the end of the day, issue resolved, credit issued and pointed questions asked yet again: WHY does a major company provide such horrible customer service. Yes, I am currently shopping around yet again.