Invalid OTP from simulation portal

I am facing this error in simulation.
Our CSR was generated through Zatca sandbox and was accepted in Developer portal.
I have ensured that the VAT No = csr.organization.identifier. and generated the OTP on simulation mode.
I am using the link : https://gw-fatoora.zatca.gov.sa/e-invoicing/simulation/compliance

In am ensuring all headers are there

Accept:application/json
OTP: 247886
Accept-Version :V2
Content-Type:application/json

When I try, First am getting : invalid OTP error - ( 2 mins after generating it)
On trying with another OTP, I am getting error 409 (conflict) : Compliance transaction was submitted/generated before.

I have also recreated CSR using the following command : fatoora -Sim -csr -csrConfig csr-config-example.properties -privateKey Key1 -generatedCsr CSR1-pem . Still not working.

in addition,We have ensured to be in Simulation mode as per the guide below.

when generating CSR using SDK, Our configuration file is as below (But replacing the details with actual details of the customer)

csr.common.name=TST-886431145-399999999900003
csr.serial.number=1-TST|2-TST|3-ed22f1d8-e6a2-1118-9b58-d9a8f11e445f
csr.organization.identifier=399999999900003
csr.organization.unit.name=3999999111
csr.organization.name=DEMO COMPANY LTD
csr.country.name=SA
csr.invoice.type=1100
csr.location.address=12211
csr.industry.business.category=IT

We have tried even in postman but still the above error.