USA only.
I needed to change my address so I logged into SSA. There is no longer 2 addresses as before, physical and mailing. I am only allowed to "contact us" which is now Ai. I haven't tried yet as the Ai is resting for the night.
For the only time in 7 years and with no banking changes, I received the "proof of life" (aka SSA 7161) letter so I need a correct address.
There was also a notice online that letters can no longer be sent to the US. I emailed the FBU in Manila but they are overwhelmed so I don't expect to get any answers.