Steps to reproduce:

1. Use the add host method "configuration.export":
   {"zabbix_export": {"version": "6.4", "hosts": [
   Unknown macro: {"host"}

   ], "groups": [\{"name": "Devices/10.12.23.0"}], "interfaces": [\{"ip": "10.12.23.139", "interface_ref": "if1"}], "tags": [\{"tag": "Device", "value": "XPro"}, \{"tag": "Subnet", "value": "10.12.23.0"}, \{"tag": "Model", "value": "Device X Pro"}], "status": "ENABLED", "inventory_mode": "DISABLED"}]}}
   Template "DeviceXPro" has linked template "DeviceCustom", in turn "DeviceCustom" has linked templates "ICMP ping" and "Device get metrics". Device get metrics has external check item. 
   Template "DeviceXPro" connected to more than 100 hosts, everything works for them
   ProxyConfigFrequency=60

Result:
See screenshot "Nodata screen 1,2". We do not receive data for more than 2 hours
After pressing Execute now, we receive the data in the next second, screenshot "Data screen 1"