Google Play Subscription Cancelled but IQTest Still Bills $9.99

I had a monthly IQTest subscription that I purchased via the Google Play Store for 9.99, and although I cancelled this subscription, I was still charged afterwards. I deleted the app and made sure to cancel the subscription through my Google Play account, so I was surprised to see that a new charge was taken on 3-9-26. In my Google Play subscriptions, the IQTest plan appears as cancelled and not active, yet the payment was still processed. I consider this charge unfair because I had already cancelled the service and was no longer using it. I request that this incorrect charge be refunded and that my subscription be fully terminated so that no further payments are taken from my account.