How to use the rhea-promise.message.decode function in rhea-promise

this._context.namespace.connectionId,
        request.body
      );
      log.mgmt(
        "[%s] Acquiring lock to get the management req res link.",
        this._context.namespace.connectionId
      );
      await defaultLock.acquire(this.managementLock, () => {
        return this._init();
      });

      const result = await this._mgmtReqResLink!.sendRequest(request);
      if (result.application_properties!.statusCode !== 204) {
        const messages = result.body.messages as { message: Buffer }[];
        for (const msg of messages) {
          const decodedMessage = RheaMessageUtil.decode(msg.message);
          const message = fromAmqpMessage(decodedMessage as any);
          message.body = this._context.namespace.dataTransformer.decode(message.body);
          messageList.push(message);
          this._lastPeekedSequenceNumber = message.sequenceNumber!;
        }
      }
    } catch (err) {
      const error = translate(err);
      log.error(
        "An error occurred while sending the request to peek messages to " +
          "$management endpoint: %O",
        error
      );
      // statusCode == 404 then do not throw
      if (error.name !== ConditionErrorNameMapper["com.microsoft:message-not-found"]) {
        throw error;

);
      log.mgmt(
        "[%s] Acquiring lock to get the management req res link.",
        this._context.namespace.connectionId
      );
      await defaultLock.acquire(this.managementLock, () => {
        return this._init();
      });

      const result = await this._mgmtReqResLink!.sendRequest(request);
      const messages = result.body.messages as {
        message: Buffer;
        "lock-token": Buffer;
      }[];
      for (const msg of messages) {
        const decodedMessage = RheaMessageUtil.decode(msg.message);
        const message = new ServiceBusMessage(
          this._context,
          decodedMessage as any,
          { tag: msg["lock-token"] } as any,
          false
        );
        if (message.lockToken && message.lockedUntilUtc) {
          this._context.requestResponseLockedMessages.set(
            message.lockToken,
            message.lockedUntilUtc
          );
        }
        messageList.push(message);
      }
      return messageList;
    } catch (err) {