ESP32 Pico-D4 problem with using special GPIO Pins

[Dr. 水文学家]

I designed my ESP32 Pico-D4 PCB board days ago. After completed it actually, I tried upload programs and test its functions and seems everything was good, until I used GPIO 17, attached a led with GPIO 17 and GND, The CPU begin to inffinity reboot and logging errors, errors were:

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1. rst:0x10 (RTCWDT_RTC_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
2. configsip: 188777542, SPIWP:0xee
3. clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
4. mode:DIO, clock div:1
5. load:0x3fff0030,len:1284
6. load:0x40078000,len:12836
7. load:0x40080400,len:3032
8. csum err:0x12!=0xba
9. ets_main.c 371
10. ets Jun 8 2016 00:22:57

GeSHi © Codebox Plus Extension

If I disconnect the led it won't reboot. Similar problem happens with GPIO 16, No error logs but led in GPIO 16 won't work.

Otherwise, I tried using UART2 which default Pins are 16 and 17. Then the cpu start to reboot with another errors:

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1. rst:0x7 (TG0WDT_SYS_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
2. flash read err, 1000
3. ets_main.c 371

GeSHi © Codebox Plus Extension

If I switch UART2 Pins to 13 and 15, The CPU works normally without any problem.
This kind of problem really comfused me ! Have someone encounted same problem?
Here's the blueprint of my PCB and the photo of my board.

[ESP_Sprite]

Ref PicoD4 datasheet, end of chapter 2.2:

Pins IO16, IO17, CMD, CLK, SD0 and SD1 are used to connect the embedded flash, and can not be used for other purposes. For details, please see Section 6 Schematics.

[Dr. 水文学家]

Thanks ! Your kindly reply really helps me a lot!