Nationwide Trying to add charges after contract was completed. Internet

My wife and I bought a house back in Oct 2010. We went through Nationwide Insurance.

Our policy was from 10-18-10 thru 10-18-2011. Our insurance is escrowed in and has been since we bought our house.

When I talked to our agent he was going to write a policy for our house for $155,000.00.

After we got our home owners insurance squared we were good for a year.

Come Oct 2011 we were looking about for different insurance. We came across Traveler's insurance. We talked to Traveler's and had them pull a quote for us.

We decided to go with Traveler's and the agent said everything will switch over on 10-18-11.

We get a call from the traveler's agent a few days later and he tells us Nationwide wrote our policy for $104,956.00! I was furious!. They shorted our house by $50,000.00!

If something would have happened to our house we would have been out $50,000.00

Nationwide said we had a policy change right before our contract ended and our escrow doesn't cover it... 

They are trying to charge us an extra $174 after our policy was up and we changed companies.

I was told on numerous occasions that if we provided proof that we had insurance from 10-18-11 going forward they would take care of the fees. I scanned and emails our proof from Traveler's that we had new insurance. 

I didn't hear anything until just a few days ago when I got an alert Nationwide had hit our credit for 60 points!
My wife and I have been working at our credit to get it up high enough to buy a new vehicle which we really need.

I talked to a lady last week who said if he send them our proof they will take care of the fees and send in that the fees and collection was not our fault.

So I promptly sent it in. 

I talk to another lady the next day and then she says, the charges are valid and you have to pay them. They took affect even though you switched insurance companies.

We have sent in the proof that Nationwide wanted twice and now they are saying we owe it even with proof of insurance change.