connection becomes down every few days i must restart Merak to come back again

[Tamer_MERAKI]

please  how can i find a solution for this problem connection becomes down every few days i must restart Merak to come back again

[GIdenJoe]

First: Is your LAN connection TO your Meraki going down or is the WAN connection of the Meraki towards the going down?

Second what kind of connections or spanning-tree topology are you running in front or behind of the MX?

[Tamer_MERAKI]

the WAN CONNECTION is down 

the design is as following:

[GIdenJoe]

Ok that was question 2.

How about question 1.

Does the MX itself lose connectivity to the internet (orange led).

In this case you'll need to log in into the 4G internet device and see if the internet is still up and if connection and IP's are still ok between it and the MX.

Or do your devices lose connectivity to the MX (MX keeps a white led).

[Tadpole86]

What happens if you reboot the 4G internet device instead of the Meraki MX? If the internet comes back online by doing that then it is the device in front of the MX that is likely a problem. I have seen this before with buggy home hubs in front of the MX.

Your question and description is not particularly clear so its not that easy to help you