Product: Credit card or prepaid card

Ive been diligently paying off my balance on my Best Buy card. When covid quarantine hit in XXXX i started paying all my credit cards on the day i received my direct deposit into my bank account to make sure they got paid each month. I also started paying more than the balance due to pay off my balance and alleviate XXXX payment due each month. My friend in XXXX died on XXXX XX/XX/XXXX from the virus and i have XXXX and XXXX so i am at an increased risk to get a severe case or die if i get infected. 
What I didnt realize was that best buy c/o citibank was applying my monthly payments to the previous months cycle starting in XXXX when they attributed my XX/XX/XXXX payment as a second payment to the XXXX billing cycle and then assessing me a late fee for XXXX. Apparently citibank closes each months billing cycle on the XXXX of the following month. The Best Buy app doesnt alert you to which billing cycle your payment will be credited to when making your payments online, nor does it say youre making a XXXX monthly payment. Neither does best buy/citibank send you an email or alert you that a late fee has been assessed to your account. Each month the late fee is increased. 
I caught the late fees and called to speak with best buy citibank. They said they could only remove XXXX late fee and it was my fault for not understanding that the payment due date and the billing cycle closing date are XXXX different dates. 
I spoke with multiple people on XX/XX/XXXX. I asked to get a callback from a senior account XXXX to discuss the situation. I was told i would get a callback the following day. I did not receive XXXX. I called back and again spoke with multiple representatives and recorded the conversations and disclosed that i was recording the call. I told the gentlemen that XXXX payments were credited to XXXX when i intended XXXX to pay applied to XXXX and that i was since then being assessed late fees each month for paying too early on each month. He kept putting me on hold to review my account. He insisted that he only saw XXXX payment per month and the late fees were justified. It was only when i looked up the dates of payments applied to the XXXX billing cycle that he was able to see the XXXX payments. When i asked to speak with a senior account manager he kept placing me on hold, returning to ask me to wait longer, and then he just hung up on me. I still havent been contacted by any senior account rep. 
In XXXX, best buy citibank sent out a lengthy email statement saying they were working hard to assist their customers during the pandemic and i have enclosed screenshots. 
So how are they helping me by applying payments to the previous billing cycle, assessing me late fees totally almost {$150.00} and refusing to understand my intentions at paying early, refusing to adjust my payments, and remove the late fees, and either not having a senior account rep return my call or disconnecting me?!!! 
This is a deplorable and opportunistic way to assess more debt to a customers account during an pandemic where they give lip service to trying to help their customers and offering postponement of monthly payments if requested due to financial hardship. I am disgusted!!!