diff --git a/gradle.properties b/gradle.properties
index f32f751bd..6f6a62feb 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,7 +1,7 @@
 # style guide
 kotlin.code.style=official
 # config
-mirai_version=0.6.1
+mirai_version=0.7.0
 kotlin.incremental.multiplatform=true
 kotlin.parallel.tasks.in.project=true
 # kotlin
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/internal/ContactImpl.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/internal/ContactImpl.kt
index 1b0a492bd..189f9d466 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/internal/ContactImpl.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/internal/ContactImpl.kt
@@ -7,10 +7,7 @@ import net.mamoe.mirai.Bot
 import net.mamoe.mirai.contact.*
 import net.mamoe.mirai.contact.data.Profile
 import net.mamoe.mirai.event.subscribeAlways
-import net.mamoe.mirai.message.Message
 import net.mamoe.mirai.message.MessageChain
-import net.mamoe.mirai.message.chain
-import net.mamoe.mirai.message.singleChain
 import net.mamoe.mirai.network.protocol.tim.packet.action.*
 import net.mamoe.mirai.network.protocol.tim.packet.event.MemberJoinEventPacket
 import net.mamoe.mirai.network.protocol.tim.packet.event.MemberQuitEvent
@@ -26,11 +23,6 @@ import kotlin.coroutines.CoroutineContext
 internal sealed class ContactImpl : Contact {
     abstract override suspend fun sendMessage(message: MessageChain)
 
-    //这两个方法应写为扩展函数, 但为方便 import 还是写在这里
-    override suspend fun sendMessage(plain: String) = sendMessage(plain.singleChain())
-
-    override suspend fun sendMessage(message: Message) = sendMessage(message.chain())
-
     /**
      * 开始监听事件, 以同步更新资料
      */
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/protocol/tim/packet/action/AddContact.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/protocol/tim/packet/action/AddContact.kt
index aee96810f..82cb97aec 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/protocol/tim/packet/action/AddContact.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/protocol/tim/packet/action/AddContact.kt
@@ -9,6 +9,7 @@ import net.mamoe.mirai.network.protocol.tim.TIMProtocol
 import net.mamoe.mirai.network.protocol.tim.packet.*
 import net.mamoe.mirai.network.protocol.tim.packet.event.EventPacket
 import net.mamoe.mirai.utils.io.*
+import net.mamoe.mirai.withSession
 
 
 /**
@@ -87,26 +88,27 @@ object CanAddFriendPacket : SessionPacketFactory<CanAddFriendResponse>() {
         writeQQ(qq)
     }
 
-    override suspend fun ByteReadPacket.decode(id: PacketId, sequenceId: UShort, handler: BotNetworkHandler<*>): CanAddFriendResponse = with(handler.bot) {
-        if (remaining > 20) {//todo check
-            return CanAddFriendResponse.AlreadyAdded(readUInt().qq())
+    override suspend fun ByteReadPacket.decode(id: PacketId, sequenceId: UShort, handler: BotNetworkHandler<*>): CanAddFriendResponse =
+        handler.bot.withSession {
+            if (remaining > 20) {//todo check
+                return CanAddFriendResponse.AlreadyAdded(readUInt().qq())
+            }
+            val qq: QQ = readUInt().qq()
+
+            // debugDiscardExact(1)
+
+            return when (val state = readUByte().toUInt()) {
+                //09 4E A4 B1 00 03
+                0x00u -> CanAddFriendResponse.ReadyToAdd(qq)
+
+                0x01u -> CanAddFriendResponse.RequireVerification(qq)
+                0x99u -> CanAddFriendResponse.AlreadyAdded(qq)
+
+                0x03u,
+                0x04u -> CanAddFriendResponse.Rejected(qq)
+                else -> error(state.toString())
+            }
         }
-        val qq: QQ = readUInt().qq()
-
-        // debugDiscardExact(1)
-
-        return when (val state = readUByte().toUInt()) {
-            //09 4E A4 B1 00 03
-            0x00u -> CanAddFriendResponse.ReadyToAdd(qq)
-
-            0x01u -> CanAddFriendResponse.RequireVerification(qq)
-            0x99u -> CanAddFriendResponse.AlreadyAdded(qq)
-
-            0x03u,
-            0x04u -> CanAddFriendResponse.Rejected(qq)
-            else -> error(state.toString())
-        }
-    }
 
 }