diff --git a/core/blockchain.go b/core/blockchain.go
index 7c2cc82bd2..c21edb7257 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -1257,11 +1257,7 @@ func (bc *BlockChain) PrepareBlock(block *types.Block) (err error) {
 		log.Debug("Stop prepare a block because inserting", "number", block.NumberU64(), "hash", block.Hash(), "validator", block.Header().Validator)
 		return nil
 	}
-	var fullVerify bool = false
-	if bc.chainConfig.IsTIPSigning(block.Number()) {
-		fullVerify = true
-	}
-	err = bc.engine.VerifyHeader(bc, block.Header(), fullVerify)
+	err = bc.engine.VerifyHeader(bc, block.Header(), false)
 	if err != nil {
 		return err
 	}
diff --git a/eth/backend.go b/eth/backend.go
index 15ea2d01ad..9167e86c12 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -247,8 +247,8 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 				}
 				header := block.Header()
 				sighash, err := wallet.SignHash(accounts.Account{Address: eb}, posv.SigHash(header).Bytes())
-				if err != nil {
-					log.Error("Can't get signature hash of m2", "err", err)
+				if err != nil || sighash == nil {
+					log.Error("Can't get signature hash of m2", "sighash", sighash, "err", err)
 					return block, false, err
 				}
 				header.Validator = sighash