DSTV bullying tactics for dish and decoder insurance

I had several calls from *** offering insurance cover on my DSTV decoder and dish. I was interested but requested details in writing via email. According to the agents "this wasn't going to happen".

The "way it works" according to the agents was that I first had to agree to this insurance after they read the conditions to me. Only then would written details be provided and I had one day to cancel.

When I said I was uncomfortable with this, the agent said that my details would be deleted from their database and I would no longer be eligible for the insurance.

Is this acceptable?