MKR Wifi 1010 + Lan Shield do not work from external power supply only from USB

Arduino MKR Wifi 1010 together with MKR Ethernet shield do not work from external power (voltage is 5V, connected to VIN). In this case, all the LEDs on both shields are lit, as usual. One MKR Wifi from external power is working fine. If the sketch does not use Lan Shield everything works. Also, from USB power MKR Wifi works well together with Lan Shield. Please help to understand what is the matter.
with respect,
Michael.

Сlarification. MKR Wifi 1010 also does not work from external power (pin VIN) if Wifi is used. Sketches where Wifi is not used ("blink" etc) work with any power connection. When you connect power to the + 5V pin, all sketches work fine.