Frustrating contract renewal process

I was contacted to upgrade my account. I don't have high data usage and actually wanted to downgrade my data bundle but was told I can't downgrade I can only upgrade. Many calls later, I am being billed the new upgrade rate with no upgrade and no tablet and a 36 month contract that I opted out of. I keep receiving messages - one of them being that my upgrade is complete and yet I chose not to upgrade. It is not easy to make contact to have this sorted out.