Solved the problem with migration.
When you change a Security Management Server , the new Active Security
Management Server can have an older Policy Assignment Table (PAT) version than the clients.
If the PAT version on the server is lower than the PAT version on the client, the client will not
download policy updates.
To fix this, update the PAT number on the Active server.
To get the PAT version:
If the Active Security Management Server is available, get the last PAT version from it.
On the Active Server:
Run: uepm patver get
If the Active Security Management Server is not available, get the last PAT version from a client
that was connected to the server before it went down.
On the client computer:
1. Open the Windows registry.
2. Find HKEY_LOCAL_MACHINE\SOFTWARE\CheckPoint\EndPoint Security\Device
3. Double-click the PATVersion value.
The Edit String window opens.
4. Copy the number in the Value data field. This is the PAT version number.
To change the PAT version on the server:
1. Open a command prompt.
2. Run the Endpoint Security Management Security utility (uepm.exe) and set the new PAT
uepm patver set <old_PAT_version_number> + 10
3. Make sure the new PAT version is set by running:
uepm patver get
In my example patver on server was lower then the clients.
I have set it to 1000 with command uepm patver set 1000 , followed by cpstop;cpstart;
After that client started showing in the dashboard.