I've created a simple form which allows users to select a name from the table and provide some details + a file upload. After the form is submitted I update the record (leads to a duplicate record being created, but ignore this issue for now).
I've now had over a thousand submissions via my bio link in instagram, but around 20-35% of people complain that they get a "page not found" message after submitting. I have tried this out and this only happened to me once when testing after I opened the link in the instagram browser (as opposed to opening it in Safari).
Anyone know what this issue could be, i don't have a url redirect on form submissions so it should just be displaying the thank you message I have written.