Unable to serially communicate with STM32F103 using FTDI module

The connections I have made are:

STM32 <----> FTDI
5V <---> Vcc
G <---> GND
PA9 <---> RX
PA10 <---> TX

I use the Arduino IDE for uploading the code. But there is no response on the serial monitor. Further, there are no voltages on the Serial RX TX pins of the MCU (checked with a multimeter). This applies to all pairs of RX TX on the MCU (A9-A10, B6-B7, A2-A3, B10-B11). I also tried to upload a bootloader file using STM32CubeProogrammer. But there as well the FTDI module could not connect. I got the following error:

12:51:19 : Serial Port COM3 is successfully opened.
12:51:19 : Port configuration: parity = even, baudrate = 9600, data-bit = 8,  stop-bit = 1.0, flow-control = off
12:51:21 : Timeout error occured while waiting for acknowledgement.
12:51:21 : Timeout error occured while waiting for acknowledgement.
12:51:21 : Error: Activating device: KO. Please, verify the boot mode configuration and check the serial port configuration. Reset your device then try again...

Due to this, I uploaded a short code to check serial connectivity using STLink and then disconnected the STLink and powered the MCU using USB(5V) and connected the RX TX from STM32 to the FTDI module to see if I get a response in the serial monitor. But this failed too and I did not get a response. This is the short code I uploaded:

void setup()   { Serial.begin(115200); }
 void loop()    { Serial.print("A"); }

I also used putty.exe to check the serial communication with FTDI. I shorted the RX TX on the FTDI and was able to echo whatever I typed. So the communication was established.

Can anyone please tell me what the problem seems to be? I have evidence to believe all components are in working condition.

Are you sure that the TX and RX lines are properly connected and not reversed?

Which core are you using? There are several cores for the STM32F103. And which board?
The STM32F103 processors have a native USB interface, and usually Serial.begin / Serial.print uses the native interface.

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