Complaint sub-issue: Problem with convenience check

XX/XX/XXXX I called Discover with the following issue : -In XX/XX/XXXX I received a promotion whereby use of a convenience check for balance transfer would be at 4.99 % promo APR ( on balance transfers for 15 months ) and with a {$0.00} promo fee -The promo offer contained 4 convenience checks ; two for program described above ; two for another promo -In early XXXX I used a check for the 4.99 % APR program to pay a balance with XXXX, for {$4000.00} and while I can not recall exact mail date it was posted by Discover on XX/XX/XXXX a current statement shows -The same statement ( dated XX/XX/XXXX and intended to be an attachment to this or can be provided ) is the point of concern as it indicates a rate of 24.99 % for a balance of {$2800.00} ; another 12.99 % for {$3300.00}. Nowhere could I find 4.99 %. 
- As well as the interest being way off and the balances not making sense there was also a 'Cash Advance ' fee of {$200.00} - I called Discover at XXXX at XXXX XXXX  ( EST ) today, XX/XX/XXXX. 
-Connected to XXXX ( in XXXX XXXX XXXX ). Very polite and after a long set of holds could not figure it out but did say this was from a prior promotion that had expired so it became a 'cash advance '. 
-I then said to XXXX something I repeated to all the people who followed : " I have in my hand the promo offer, with the 3 remaining checks and on one page the perforations are as clear as can be for the check I used. The promo not only has not expired, it is actually still open to me ( until XX/XX/XXXX ). '' -XXXX couldn't figure it out and moved it to 'XXXX ' in 'Disputes Team '. I told him about the checks & promo in hand and he ultimately said the same as XXXX ; that it was an expired promo. At this point let me say I may be XXXX but I don't think I am incompetent and knew what was in my hand as to the promo materials- plus i recalled shredding a prior Discover promo. I don't use these 'promo 's ' lightly. I asked XXXX what next. 
-XXXX  transferred me to 'XXXX ' in 'Billing Assistance '. After once again repeating the situation as stated above, and putting me on many holds she asked if I had a copy of the check. I explained that I don't have a copy of a check I sent and that while I kept the whole promo solicitation I never imagined I would need to make a copy of the check itself- I'm glad i kept the rest of that promo however. ) Ultimately she said all she could do was this : ( A ) She would need an image of the check and would request same. 
( B ) I asked when or how long will that be. This is a direct quote : " There is " no timeline ( she ) could give for when they would get the check ''. ( I was stunned and repeated that back to her and she said I got that right- no timeline ). I said that is not acceptable ( C ) XXXX then said, as to her requesting said check, and I use an exact quote : " IF you get the check you can dispute it at that time '' I said " IF? '' and she said words close to " well, when ''. Again, however, no timeline ( D ) As to Discovers getting copies of these checks she explained something about merchants being allowed 30 days even though they need not reply at all ( I don't understand it's relevance, if any, to me ) but then repeated that stunning ( to me ) statement about how for the consumer " there is no timeline. '' ( E ) Summary of the call after 54 minutes was they " may '' get the check copy to me and only then can I file a dispute. She wouldn't be getting a copy too and that was it. I expressed how utterly inequitable that is to their customers. She said she would 'send a note ' about that. To who it would be sent I was not told nor did it seem of much concern or matter. Before ending the call she did agree if this was her she wouldn't be satisfied either. 

As it stands now I am being charged as much as 20 % MORE than the promo check, plus apparently I was charged a fee for the 'cash advance '.