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I checked all the links regarding this problem on Stackoverflow

I have the same problem but from what I was able to debug, I can read the data using QModMaster with no problem. The send data from the QModMaster and from my script is identical, still, I am unable to receive a proper response.

Below you can see my code:

from pymodbus.client.sync import ModbusSerialClient as ModbusClient
from pymodbus.constants import Endian
from pymodbus.exceptions import ConnectionException
from pymodbus.payload import BinaryPayloadDecoder
import time
import logging
import logging.handlers as Handlers
logging.basicConfig()
log = logging.getLogger()
log.setLevel(logging.DEBUG)
METHOD = 'RTU'
COM_PORT = 'COM7'
STOP_BITS = 1
BYTE_SIZE = 8
PARITY ='N'
BAUD_RATE = 9600
TIMEOUT = 1
client = ModbusClient(method=METHOD,
                       port=COM_PORT,
                       stopbits=STOP_BITS,
                       bytesize=BYTE_SIZE,
                       parity=PARITY,
                       baudrate=BAUD_RATE,
                       strict=False,
                       timeout=TIMEOUT,
WORD_ORDER = Endian.Little
BYTE_ORDER = Endian.Big
while True:
    connection = client.connect()
        print('Reading...')
        print(f"Connection is {connection}, socket is {client.is_socket_open()}")
        values = client.read_holding_registers(address=0x0,count=0xA,unit=0x1)
        print(values.registers[0])
        print(values, values.registers)
    except ConnectionException as ce:
        print("CE ERROR")
        # print("===ERROR=== \nPort cannot be accesed \n",ce)
    except AttributeError as ae:
        print("AE ERROR" , ae)
        connection = client.close()
    logging.basicConfig()
    log = logging.getLogger('pymodbus.server')
    log.setLevel(logging.ERROR)
    log = logging.getLogger('pymodbus')
    log.setLevel(logging.ERROR)
    handlers = [
        Handlers.RotatingFileHandler("logfile", maxBytes=1024 * 1024),
        Handlers.SMTPHandler("mx.host.com",
                             "pymodbus@host.com",
                             ["support@host.com"],
                             "Pymodbus"),
        Handlers.SysLogHandler(facility="daemon"),
        Handlers.DatagramHandler('localhost', 12345),
    [log.addHandler(h) for h in handlers]
    time.sleep(1)
And my debug log:
DEBUG INFO
And here is the send request from QModMaster and also the response in the background
QModMaster Working
Any idea why this is happening? I tried with different USB-Serial cables, and also with different devices. The problem is the same.
So I managed to find a solution using this post: LINK
The post suggested that a delay between connection and reading would be recommended "You can try running the serialclient with a start up delay after it open
the port then doing a "stty -F /dev/ttyUSB0 crtscts", and see if that works."
This is what I did, and it worked!
while True:
connection = client.connect()
time.sleep(2)
    print('Reading...')
    print(f"Connection is {connection}, socket is {client.is_socket_open()}")
    values = client.read_holding_registers(address=0x0,count=0xA,unit=0x1)
    value = ((f'Modbus error: {values}') if values.isError() else values.registers)
    print(values.registers[0])
    print(values, values.registers)
        
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