Product: Credit card or prepaid card

I disputed a {$5900.00} charge made on XX/XX/XXXX from XXXX XXXX for a XXXX XXXX XXXX on a vehicle i had purchased. Dispute XXXX. The service contract i received via email & also the hard copy in the mail was not readable because the right side of every line on 11 page contract was cut off & couldn't be read. I communicated with XXXX XXXX on many emails & finally told them i was disputing this charge with Citi Visa to get my {$5900.00} refunded. XXXX XXXX discussed this with their Gen Mgr & CFO & agreed not to challenge my dispute & allow a chargeback from Citi bank to occur. They said they cancelled the contract & i submitted all this info  to Citi. Meanwhile i found another vendor & bought this same contract from them & received a fully legible copy of the contract w/o issue. Meanwhile i have 2 charges on my account. 
I disputed the charge with Citi Visa & it was conditionally reversed on XX/XX/XXXX. On XX/XX/XXXX I submited info to Citi bank explaining what happend with many emails as attachments between XXXX XXXX & I. This included the response from XXXX XXXX that they would not content/challenge my dispute of the charge and would allow the chargeback to proceed without issue and info that showed they cancelled the contract. 
On XXXX Citi Visa told me on a statement i viewed online ( after i called them ) that said they could not read my emails. They said they found the charge to be appropriate & subsequently reversed the conditional credit and re-charged my account. I immediately wrote a letter contesting this recharge of {$5900.00}. to my account and again explained that the vendor XXXX XXXX had agreed to let the dispute charge be reversed since they cancelled the contract and attached the relevant email from XXXX. I again disputed the {$5900.00} charge. I followed up with 2 phone calls to Visa dispute section explaining this and challenging their determination. I also challenged their process explaining that if they could not read the 3 emails & many attachments i submitted to support my dispute, why/how they determined that my case was closed and re-instated the charge. I said an appropriate response from Citi would have been to contact me to say they could not read the info- not merely considered the dispute resolved & rechrging my account. 
I subsequently sent by mail copies of everything again & they acknowledged receipt of my mail. Meanwhile my XXXX statement closed on XX/XX/XXXX with the {$5900.00}. charge reversed & on my statement again saying " the conditional credit was reversed since it was determined to be a valid charge ''. 
Why would Citi reinstate the charge because you couldn't read my email instead of contacting me to indicate a problem. 
XXXX XXXX has indicated that they will not contest my dispute & will allow the chargeback of {$5900.00} to occur without any issue. The vendor has agreed with my dispute to allow a chargeback to occur and not contest it- However apparently Citi considers this issue resolved and will not initiate a chargeback. I do not understand why this charge was re-instated & contest this reinstatement. The company XXXX XXXX through-XXXX XXXX & their CFO & General Mgr has told me they will allow the chargeback to occur without protest/contesting it as a way of cancelling the XXXX Contract. 
Why was this charge re-instated on XXXX & when will it be taken off my account.