Issues with CA

Hello,

We are a private limited company and have a CA since more than a decade but since past few years he isn't providing proper service but asking for hike in fees every year to the time to 20%.

Would request some experts to guide on a few points:
1. What's the responsibility of CA in getting back refund from IT? we have pending refunds of 3 years (not latest, around 4/5 years back) but all the CA is doing is writing an email for same and not taking up any responsibility of getting the same to us.
2. He is constantly ignoring our emails for all pending matters.
3. If we plan to change our auditor, do we require an NOC from the CA to amend details in ADT form?
4. He tries to evade from this basic responsibilities like proving a stamped n signed copy of complete set of audit report. He intends is to take a print out of the set in copies and go to him to get it signed and provide him the same too!
5. We haven't cleared his full payment and a particular amount had been kept on hold in lieu of the pending refunds. He wouldn't provide an NOC till we clear the payment and if we clear his full payments, none of our pending issues would be cleared by him. What's the solution to this??

If experts could kindly guide of financial responsibilities that a CA has and if he doesn't fulfill those & refuses to give NOC, can any action be taken against him?


Thanks in advance,
Kavita