Try Juvederm Ultra

Perlane is a thicker Restylane and might be used but your lip might not need a thick product. Longer term fillers have greater risks of lumps and bumps, some could even be permanent, such as Silicone. You have to be very concerned about using a long lasting filler in the lip in case you don’t like the result! You should try Juvederm Ultra, and although it is a hyaluronic acid, similar to Restylane, it may react differently in your body and last a little longer.

While restylane is a good hyaluronic acid filler for the lips, there are others that last longer. Perlane and juvederm ultraplus will definitely last more than 2 months in the lip.