National Insurance Company — Medical claim

I'm suffering from Multiple Sclerosis and I'm a staff of a public sector company - Bank of Baroda. I'm having a group health insurance of national insurance company and TPA is Medi Assist. In their policy my disease is included for 100% reimbursable whether it is Pre-hospitalization, hospitalization or Post-hospitalization. Even domiciliary hospitalisation is also 100% reimbursable. Last year my claim was paid by the insurance company but this year they rejected it by mentioning it as a day care treatment. I was going for OPD as a lot of blood tests and different types of tests were there included MRI. Then doctor advised to get admitted because they were going to start treatment with a new medication - Rituximab inj. as drip. And as it is a new medicine I should have been under observation. I was hospitalised for 25 hrs, which is clearly mentioned in the discharge summary. In their policy MS is clearly written in the list of diseases covered. Then why such type of contradiction like one year they will cover and the other they won't. Although in the renewed policy nothing has been modified. In my MRI report the disease is clearly mentioned as RRMS which stands for Relapsing-Remitting Multiple Sclerosis. My doctor in the admission form had written MS. For MRI test it was written MS - protocol. Only in discharge summary they didn't mention properly. They could have asked me for clarification. I could have got it rectified from the hospital. But they didn't raise any query. And they recommended for repudiation. I need my claim reimbursed as soon as possible. If any letter they need from the doctor or any other documents they require I'm ready to provide. My policy no is[protected] and my claim ID is 28592416.