I created a Freshphone account for myself and registered successfully on a Grandstream HT801 device. I made some calls to check the system and all was working well.
I then created another Freshphone account for my father, and tried to register the phone by entering his account details on the same HT801 device. The device failed to register on his account. I checked my account and there was no device registered there.
I then loaded the app on my smartphone, and registered my account on there. The device registers on my account.
I then soft reset the Gransdstreamer HT801, and re-entered my father's account details into it. But still, it fails to register.
Please advise how I may resolve this problem
I have subsequently done a firmware upgrade and hard reset on the device, re-entered the account details of my fathers's account, and still the phone is not registering.
I can log into the FreshPhone account profile of my father, and the browser based soft phone does register, and make a call, as well as receive a call.
I cancelled the account on my father's profile, and created a new number. Still did not work
Read up on SIP ALG setting on the router, and saw it was enabled. I disabled the setting, rebooted the router, and the phone registered. It then disappeared again.
Suddenly I remembered I changed routers between trying my account and my father's account, so that I could use data on another ISP server.
I reverted back to the router I used initially, and the phone has now registered on my father's account. Turns out the router is the source of error. The router must be up to date on SIP protocol/settings for phone registering to work correctly.
Read up on and NAT settings for SIP ALG and SIP Passthrough states for the router, and found that ALG must be disabled, and SIP Passthrough must be enabled.