OP, question your agent further. His/her business is 'insurance', and he should be able to direct you accordingly. If no luck there, do some 'shopping' and be prepared to see a spike in premium. Also check with whoever carries your 'homeowners' to see if there is a rider available. That coverage will take some looking for, it's a common exclusion.
Also, typically an 'agent' represents only specific insurance companies, and they are beholding to the company they represent. Try to find a 'broker' who is somewhat bound to represent you and your interests, versus those of an insurance company. Think about that, there is a big difference. Of course it all depends where you live, but you will find that subtle difference in most places. (I speak as having been at different times an agent, a broker, and a producer. I hope this helps a little).