diff --git a/programs/zk-token-proof/src/lib.rs b/programs/zk-token-proof/src/lib.rs
index 7578b03266..d7c791c76c 100644
--- a/programs/zk-token-proof/src/lib.rs
+++ b/programs/zk-token-proof/src/lib.rs
@@ -56,7 +56,7 @@ pub fn process_instruction(
             verify::<WithdrawData>(invoke_context)
         }
         ProofInstruction::VerifyWithdrawWithheldTokens => {
-            ic_msg!(invoke_context, "VerifyWithdraw");
+            ic_msg!(invoke_context, "VerifyWithdrawWithheldTokens");
             verify::<WithdrawData>(invoke_context)
         }
         ProofInstruction::VerifyTransfer => {
diff --git a/zk-token-sdk/src/zk_token_proof_instruction.rs b/zk-token-sdk/src/zk_token_proof_instruction.rs
index 3dfdea18de..5bcd653967 100644
--- a/zk-token-sdk/src/zk_token_proof_instruction.rs
+++ b/zk-token-sdk/src/zk_token_proof_instruction.rs
@@ -73,7 +73,7 @@ impl ProofInstruction {
     }
 
     pub fn decode_type(input: &[u8]) -> Option<Self> {
-        FromPrimitive::from_u8(input[0])
+        input.get(0).and_then(|x| FromPrimitive::from_u8(*x))
     }
 
     pub fn decode_data<T: Pod>(input: &[u8]) -> Option<&T> {