LL insurance for room renting

I hope this is the right place for this post. We are currently renting by rooms to student (total of 4 rooms = 4 different leases). When we purchased the IP I took out insurance through my lenders; but 4 months down the track they refunded my money saying that they underwriting guidelines did not cover room renting. Since then I took out a special LL insurance with Allianz, it is classed as as a Landlords-EDI (I don't know what EDI is stand for) , and it covers the 4 leases. I took the cover via an insurance broker (MGA Insurance Broker), with the premium and fees of almots $2K per year (compare with about $1300 forr my own home and content with a similar building replacement and content values). Though I have peace in mind with the service, I am just wondering if there is a cheaper alternative out there. I found the insurance issue mind boggling/not straight forward.

Today I contacted my lender again, and they still don't have the cover I need. I called one major insurance provider, but all they offer me is building insurance (deviated from my question about LL insurance).

For those who are renting by the room, what type of insurance do you take out , which company do you use, and are you happy with them?
Try googling 'air bnb insurance' or 'sublet insurance '?
The thing is, most people who used to sublet didn't declare the income.
That's changing now with air bnb.