Hopefully I can help here.
Some smart meters can read solar, it's not something ive seen for a while in a domestic house, if you have heard of the rent a roof scheme? Years ago we would be able to 'poll' reads, however we're talking about thousands of sites.
Back to your system and question. So our app doesn't work with FIT or SEG, can I ask what scheme you're part of? or is this a new install?
By smart meter do you mean the in home display unit? Some do read the solar & some dont, I know the ivie bud is marketed as it reads the solar. Here is the link - https://ivie.co.uk/eonnext/
If you can give me some more information I will be able to help, this subject can be a bit of a rabbit hole so the more info I have here the better, 😀