Misinformation at Call centre

I called in to the retentions department and asked for a settlement on my handset. I further asked if I would be able to still receive the full benefits of my contract until its expiry, the agent assured me it was possible. I went ahead and made the payment to settle my account. To now be told I won't receive the same benefits.

These businesses should be held accountable for the things they agree to over the phone.