Good morning All
The ip address its the good one put i can not connect to mikrotik i always have this error message :"Error could not connect to 192.168.15.1"
with the Mac address its going ...
Please help

Check if the winbox access is allowed for you in /ip services.
Check your firewall for winbox port to be open for you.

i noticed that the winbox port has change ...
what can be the reason ?

i noticed that the winbox port has change ...
what can be the reason ?

Presumably you or someone else has control of your router and changed the winbox port. Consider changing the credentials. It wouldn't hurt to netinstall and reconfigure, just in case.

i noticed that the winbox port has change ...
what can be the reason ?

Can I assume that you mean that when you connect via the MAC address, you are able to see that the service port for WinBox has changed. If that is the case, you would need to specify the non-standard port. In your case, that would be connect to 192.168.15.1:nnnn - where nnnn is the actual port number. I do that all the time because I use non-standard ports for WinBox.
However as tippenring pointed out, the bigger question is how did it get changed?