This happened because when using upload_protocol = mbed, then upload_port is respected, as the path you want to copy the firmware too. If you’d want to do this manually you’d say upload_port = E:, for example.
It’s good that that upload method is working now, but then the OpenOCD upload is still not working? Without that, you also cannot use debugging, as that requires the SWD interface.
Have you tried the firmware upgrade of the STLink already? LINK Firmware version : V2J35M26 is two majors behind the current
Maybe also uninstall the driver in the Windows device manager and install them again using the latest version found in ST-Link utility (C:\Program Files (x86)\STMicroelectronics\STM32 ST-LINK Utility\ST-LINK_USB_V2_1_Driver)