Pi Pico

Thonny always report:
WARNING: Could not sync device’s clock: can’t import name RTC
WARNING: Could not validate time: can’t import name RTC
MicroPython v1.14 on 2021-02-05; Raspberry Pi Pico with RP2040

Blink works.

Pico Display just lights big white LED.

Any suggestions

The RGB LED on the Display always starts up ON with power-up. It is set up with PWM and low values give bright output. Rather confusing! You get used to it.

There is no built in Real Time Clock on the Pico.

Have you set Thonny to Raspberry Pi Pico?

Have you installed the Pimoroni Version 9 UF2 which you can get here:
Releases · pimoroni/pimoroni-pico · GitHub

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Pimoroni Pico Display Workout : 3 Steps - Instructables