How can a simple thing as start date be a complication

Took out a warranty policy on the 24th April and asked that the policy starts on the 25 May. Today I called and asked that instead of starting in May can I start the policy with immediate effect and no one could help me. I was taken from pillar to post, spoke to a few consultants and eventually was told it cannot be done and I have to wait for next month debit date. Shockingly, I was also told that I have a 3 months waiting period anyway. But at the initial stage of the policy I was told there are no waiting periods. Too many red flags, and I'm wondering if I would be assisted at claim stage.