4 months of hell before getting a response for the assessment

I took a mechanical insurance with Constantia for my car. This was done over the phone when someone called me to sell me the product. They briefly read out some points of the policy from what I gathered it was a mechanical warranty and whatever I needed to know was in the contract which they will send to me. This was in MAY and the contract never came through until I requested for it by then already having paid for three months (sent to me in August). I had a problem with the vehicle in September and took the vehicle to an RMI dealer as instructed. From then onward the company gave me the run around. I kept contacting them and sending emails and every time I send through what they asked for, I never got a response until I inquired again, and again they asked for something else. The insurance company made no effort to contact myself or the RMI dealer who even sent an assessment report. This carried on until the beginning of December when I sent an email stating I will take legal action or advice from an ombudsman. The next day an assessor went to the RMI dealer to view the gear box. The RMI dealer said that the assessor came through and took a few pictures. Again I did not hear anything from the company until I inquired and was told that they will respond on Monday. For the first time they kept their word and responded only to inform me that the claim was rejected. I did not understand why so I contacted them and was told the reason being is that the vehicle has 17' rims. Although there is a section that states Items not covered: “Any non-approved manufacturer’s modifications" as pointed out to be the reason it was declined, this contract was not given to me until 3 months after I took the cover and made payments. No one took the time to explain what will not be covered and neither did they enquirer if I had changed the rims as if this was asked of me and explained in the first place I would not have taken such a cover were I will not be allowed to claim at all because I had 17' rims added. These rims were a pre-existing on the car when the policy was taken out it is not something that I added or changed after the fact. I was not able to view the contract until 3 months after I had taken the policy. If this was to be an issue would the company not have needed to send an assessor to view the vehicle? I also have a policy with Out- Surance who never had an issue when I claimed. They never had a problem with the rims being changed. And never took months to decide if a claim was valid or not. Now 4 month after I reported a claim I am told that I will not receive assistance. I have wasted time, money with this company. Yet if I had been duly informed that I would never be able to claim due to the fact that I had 17’ rims I would obviously never have agreed to take this policy.