A low CTR but high conversion rate can be a confusing datapoint. It can often be seen with content recommendation ads. However it can be a good thing. As the reason is, potential customers are reading the headline before clicking. And if the headline is accurate, it is self selecting as to who this will be most relevant for. Then the most relevant people click through and then do convert at a higher rate.
So where you see this happening, is typically, an example of better advertising creative upfront. It may be you need to narrow your targeting to lift the CTR up. However that’s a consideration of cost, as that may increase the cost upfront.