It all depends on the condition of your dosa pan. If there is too much wear and tear on it, it'd be hard to get back the same non-stick characteristic to it. But if your pan is relatively new, you can indeed consider some of the following options. The first option is to season it well. You can smear some oil on the hot pan. Allow it to smoke for 30 seconds to a minute.  You can also use a brush to spread the oil on all sides and edges of the pan. Once it's cooled down, wipe out excess oil from the pan using a kitchen towel. Note: You don't have to wash the seasoned pan again.  The second option is to perform the same step a couple of times. Yes, it may seem a repetitive task, but it does work great! In fact, you might notice a better non-stick coating after performing this step several times. So, do try it out. The other tip to regain the non-stick characteristic is to use extra oil while preparing the dosa. The added oil will help in forming a thin layer on the pan, which should help in removing the dosas without any issue. Quick Tip: If you don't like too much oil, you may also use some cooking sprays to achieve the same non-stick characteristic. But as I said, the seasoning method is more effective and long-lasting in this case.