Comcast refuses to uphold signed contract

We worked with Comcast to come up with a contract on 12/20/2017.  We signed and returned the contract through docusign on 12/20/17.  In January the bill was not changed, I called and they said the new contract would not be applied until February.  In February the bill again was not changed, I called and they credited our company the difference and assured me that they made changes and the contract would be in affect the following month.  In March again the bill was not changed, I called and they said they mishandled the contract and because it is 3 months old I will need to sign a new contract which is at a higher in price. 

The original contract reads to me that once signed it is legally binding, so I do not understand how they can not uphold the original contract.

Our company has two accounts with comcast which totals around $800.00  a month, and we would like to avoid the hassel of changing service providers.

I keep getting placed to a 3rd party company "The Results Companies" I have spoken to a women named **** no last name would be given, and she would not let me speak to a supervisor, she just said that they will not uphold the original contract, with no reasoning behind why.  I have also received an email from her supervisor with the new contract higher in price that they want me to sign. 

We are losing our trust in Comcast and hope that this message reaches the right people to find a solution to this discouraging situation.

ZNALLC

(Update as to the request of a Comcast Agent)

I have been ask by comcast to take out the name and personal information of the the 3rd party manager's, personal information(name & email Etc)  I have also blanked out the first name of the woman who would not let me speak to the supervisor or give me reasoning on why the signed contract was not being upheld.