Sorry, but this is definitely not a hardware, connection or session issue. Just check the rest of the thread. We're seeing issues over various links (broadband, mobile, datacenter) on different server locations (AWS vs. on dev machine) with or without private mode / logging out and then in.
I honestly wish it was something like this, at least then we could fix it.
The double POST requests you see is most probably because api.instagram.com returns a 302 response ("Found", i.e. redirect). This is a relatively recent change, but still weeks before those issues started.
By the way, your server refuses connection when you go to https://picodash.com directly (without www.). You might want to fix this.
I honestly wish it was something like this, at least then we could fix it.
The double POST requests you see is most probably because api.instagram.com returns a 302 response ("Found", i.e. redirect). This is a relatively recent change, but still weeks before those issues started.
By the way, your server refuses connection when you go to https://picodash.com directly (without www.). You might want to fix this.