@OMADA-tunisia 

Could you describe your exact network topology?After you reconnected the router to the network, did you try rebooting the router—or even restarting the entire network?
When you say “the network also drops,” do you mean the whole network loses Internet access?At that moment, did you check whether your ISP is up?
And can you reproduce this issue reliably?

  @OMADA-tunisia 

Thank you so much for taking the time to post the issue on the TP-Link community!

To better assist you, I've created a support ticket via your registered email address and escalated it to our support engineer to look into the issue. The ticket ID is TKID251254446 please check your email box and ensure the support email is well received. Thanks!

Once the issue is addressed or resolved, welcome to update this topic thread with your solution to help others who may encounter the same issue as you did.

Many thanks for your great cooperation and patience!