No target found after first flash

[skip_shane]

I have a board using STM32F103CBT6 chip.  After flashing the board once (through CubeIDE v1.14.0 with ST-Link v2) I cannot flash it again and keep getting the message "No target found".  Here's a snapshot of the chip circuit:

When I power up the board it flashes an LED that I programmed so I know the initial programming worked.  But I can't connect again. Any ideas would be appreciated.

[Tesla DeLorean · Accepted solution]

Connect NRST to the debug header so "Connect Under Reset" can actually work as a method.

Try pulling BOOT0 to VCC so your code doesn't execute.

Check your code, make sure you aren't either explicitly disabling the debug interface, or reconfiguring PA13/PA14

[skip_shane]

The issue was that I did not configure PA13/PA14 before flashing the first time.  Now that I configured the pins properly the board can flash multiple times.  I'll also add a NRST pinout for this board in case this happens in the future.