I read the reviews. Found the provider I wanted. Now I’ve called and left two messages with no call back. Should I keep calling? How many calls are to many?

How many times you call is entirely up to you.

Providers get a GO-zillion calls, most of which don't end up as a revenue.  You have to realize the impetus is on you to make it happen.  Can't blame anyone else.

If she never calls back, then call backup number 1,2, etc.  Never get fixated on someone you haven't seen yet, just move on...

Thanks for the advice. I continued to call and now have an appointment set up.......Thanks

If you have ever wanted something special you may have found that it does not always come easy. There are things that happen that do not involve you.
She may be on vacation.
She may be sick.
She may not have any time on her schedule this month.
She may be busy studying for finals.
She may be on tour in another part of the country.
She may not be getting the messages.
Who knows how many things could be getting in the way of a successful connection. Keep trying the phone and try e-mail as well. You might get lucky someone may cancel. She might need an extra $1000 one week. One never knows all the reasons.