diff --git a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_csf.c b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_csf.c
index ed4f051..89b022c 100644
--- a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_csf.c
+++ b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_csf.c
@@ -134,14 +134,14 @@
 /*!
  *  \brief  Update client change-aware state based on protocol event.
  *
- *  \param  connId      Connection handle.
+ *  \param  connId      Connection ID.
  *  \param  opcode      ATT PDU type.
  *  \param  pPacket     Data packet from L2CAP.
  *
  *  \return \ref ATT_SUCCESS if client is change-aware, else \ref ATT_ERR_DATABASE_OUT_OF_SYNC.
  */
 /*************************************************************************************************/
-uint8_t attsCsfActClientState(uint16_t handle, uint8_t opcode, uint8_t *pPacket)
+uint8_t attsCsfActClientState(dmConnId_t connId, uint8_t opcode, uint8_t *pPacket)
 {
   uint8_t err = ATT_SUCCESS;
   attsCsfRec_t *pRec;
@@ -152,7 +152,7 @@
     return err;
   }
 
-  pRec = &attsCsfCb.attsCsfTable[handle];
+  pRec = &attsCsfCb.attsCsfTable[connId - 1];
 
   /* If the client is change-unaware */
   if (pRec->changeAwareState == ATTS_CLIENT_CHANGE_UNAWARE)
@@ -167,7 +167,7 @@
       /* Move client change-aware state to pending */
       pRec->changeAwareState = ATTS_CLIENT_CHANGE_PENDING_AWARE;
 
-      ATT_TRACE_INFO2("ConnId %d change aware state is %d", handle + 1,
+      ATT_TRACE_INFO2("ConnId %d change aware state is %d", connId,
                       ATTS_CLIENT_CHANGE_PENDING_AWARE);
     }
 
@@ -189,12 +189,12 @@
       /* Move client change-aware state to aware */
       pRec->changeAwareState = ATTS_CLIENT_CHANGE_AWARE;
 
-      ATT_TRACE_INFO2("ConnId %d change aware state is %d", handle + 1, ATTS_CLIENT_CHANGE_AWARE);
+      ATT_TRACE_INFO2("ConnId %d change aware state is %d", connId, ATTS_CLIENT_CHANGE_AWARE);
 
       /* Callback to application to store updated awareness, if bonded. */
       if (attsCsfCb.writeCback != NULL)
       {
-        attsCsfCb.writeCback(handle + 1, pRec->changeAwareState, &pRec->csf);
+        attsCsfCb.writeCback(connId, pRec->changeAwareState, &pRec->csf);
       }
     }
     else
@@ -227,7 +227,7 @@
         */
         pRec->changeAwareState = ATTS_CLIENT_CHANGE_AWARE_DB_READ_PENDING;
 
-        ATT_TRACE_INFO2("ConnId %d change aware state is %d", handle + 1,
+        ATT_TRACE_INFO2("ConnId %d change aware state is %d", connId,
                         ATTS_CLIENT_CHANGE_AWARE_DB_READ_PENDING);
       }
     }
@@ -235,7 +235,7 @@
 
   if (err == ATT_ERR_DATABASE_OUT_OF_SYNC)
   {
-    ATT_TRACE_INFO2("ConnId %d out of sync, PDU with opcode 0x%02x ignored!", handle + 1, opcode);
+    ATT_TRACE_INFO2("ConnId %d out of sync, PDU with opcode 0x%02x ignored!", connId, opcode);
   }
 
   return err;
diff --git a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_eatt.c b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_eatt.c
index f1ca487..f0d42a6 100644
--- a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_eatt.c
+++ b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_eatt.c
@@ -166,7 +166,7 @@
     }
 
     /* check client's status to see if server is allowed to process this PDU. */
-    err = attsCsfActClientState(connId - 1, opcode, pEvt->dataInd.pData - L2C_PAYLOAD_START);
+    err = attsCsfActClientState(connId, opcode, pEvt->dataInd.pData - L2C_PAYLOAD_START);
     if (err)
     {
       BYTES_TO_UINT16(attHandle, pEvt->dataInd.pData + ATT_HDR_LEN);
diff --git a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.c b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.c
index 36dbbd0..fa38787 100644
--- a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.c
+++ b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.c
@@ -182,7 +182,7 @@
   }
 
   /* check client's status to see if server is allowed to process this PDU. */
-  err = attsCsfActClientState(handle, opcode, pPacket);
+  err = attsCsfActClientState(pCcb->connId, opcode, pPacket);
   if (err)
   {
     BYTES_TO_UINT16(attHandle, pPacket + L2C_PAYLOAD_START + ATT_HDR_LEN);
diff --git a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.h b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.h
index 5c46da8..72927bc 100644
--- a/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.h
+++ b/connectivity/FEATURE_BLE/libraries/cordio_stack/ble-host/sources/stack/att/atts_main.h
@@ -164,7 +164,7 @@
 void attsProcValueCnf(attsCcb_t *pCcb, uint16_t len, uint8_t *pPacket);
 void attsProcReadMultiVarReq(attsCcb_t *pCcb, uint16_t len, uint8_t *pPacket);
 
-uint8_t attsCsfActClientState(uint16_t handle, uint8_t opcode, uint8_t *pPacket);
+uint8_t attsCsfActClientState(dmConnId_t connId, uint8_t opcode, uint8_t *pPacket);
 uint8_t attsCsfIsClientChangeAware(dmConnId_t connId, uint16_t handle);
 void attsCsfSetHashUpdateStatus(bool_t isUpdating);
 uint8_t attsCsfGetHashUpdateStatus(void);