Hello,
Thank you for your question.
Could you provide Troubleshoot file from RUT241? You can do it by accessing your routers WebUI > System > Administration > Troubleshoot, or in your RMS account: RMS > Devices > Select your RUT241 > Action > Export troubleshoot.
And what end device(192.168.1.157) are you trying to open the port for? Could you describe to me what are you trying to do with it?
Kind regards,
Edvinas