Hi Omar,
The communication looks ok.
One difference between the two Smart Lock generations that might affect you is the allowed MTU size.
Smart Lock 1.0 is using a maximum MTU size of 23. Therefore any message longer than 20 bytes needs to be sent via a “Write Long” request instead of a regular “Write” request.
As your first message (shorter than 20 bytes) is correctly handled and the second one (longer than 20 bytes) fails, this might be the reason.
regards,
Marc