Rain not allowing me to cancel my subscription!

I have been trying to cancel my rain internet service for three months now. I've cancelled it multiple times on the app, I've phoned three times and still the continue to take money from me, yet I'm not using the service anymore!

They had horrible reception at my flat, I've already got fibre internet yet I'm unable to cancel. They just said they will escalate with accounts and nothing happens. If they don't allow me to cancel in the next few days I'm laying a complaint with the interest service provider umbud and asking my bank to block them. WORST SERVICE EVER!