Could someone help with understanding what is going to happen to my subscription?

So, I recently subscribed to 3 months of an app called brainbuddy. Then not wanting it to renue without me noticing, I cancelled my subscription (it said that it will continue for the next 3 months).

Then when I went back into the brainbuddy app, there was a special offer for a discounted price for a month. So as I thought it would be for a limited amount of time, I subscribed to that too. On the popup that takes my face id to confirm my purchase, it did say that it renues in 4 months time. But then when I went to look in the subscription section in my apple account, it says that it renues next month.

Could anyone please explain what is going to happen to my 3 months subscription?

Also, if my 3 months subscription doesnt come into effect, who should I contact? Apple support or the app provider?