Monthly to annual

I recently bought my annual prepaid plan, as I do during black friday. When I applied the code for the annual plan, I all the sudden had 2 accounts - turns out they had different storage amounts, that was the difference. In the past, when I'd done this 'trick', the plan just gets extended. When I contacted customer service, the agent told me repeadedly that my annual prepaid was a monthly plan and that I needed to pay monthly for it. I initally had asked for a cancellation of my monthly plan and a credit - it has 2 weeks left. No matter how I tried to explain, this person kept correcting me - I, yes, have an annual plan that does not expire until Nov. 2024, but I still have to pay 19.99 a month for it. I just cancelled the monthly plan with no resolution, but am baffeled as to the level of customer service here? What do they not understand about this?? I may be unclear here, as I'm paraphrasing (I 'downloaded' the chat convo, but where did it go???), so ask any questions that you need.