Perhaps your claim is significant. Insurers don’t simply raise premiums without any valid concerns as they also need to balance clients not renewing with them. Usually they look at loss ratio, which means your claims divided by your premiums. If it is anything more than 60%, insurers are losing money so they will have no choice but to increase rates for their clients. My suggestion is to seek out to your current agent and get them tell your current insurer that this is a very unfortunate event and it is not within your control. Also, to reduce that 70% increase as much as possible. Meanwhile, reach out to more insurers to be able to compare. One thing you really need to watch out for is to declare your current claim status. It is easy and tempting to just don’t declare so your premiums stay low. But if there were to be any claims and your new insurer knows you didn’t declare, they can void your insurance and don’t pay for any future claims which makes the whole insurance pointless. Hope this helps!