No customer retention whatsoever

I called cellc a few mins ago to load BIS and whilst at it asked if they had proof of the sms being sent to me to notify of tariff increases,as I hadn't received it and had just read the t&cs stating a customer has to receive written notification of price increases and get 20 working days to cancel the contract without a cancellation charge.So I asked to cancel both my contracts and get transferred to retentions,I don't know why you even call it that because the department doesn't even attempt to save loyal customers.I'm still deciding if I should pay and cancel or just let the pathetic contract finish and you've lost a customer