ok, very good, was just a idea to help.
now i see your processing code,
can you pls repair this post using the
</> code formatter
ok, and what is the question?
why you not use a
String serialStr = port.readStringUntil(’\n’);
println(serialStr);
to understand what is wrong?
if i look your arduino code ( what actually not send a good CSV line )
value=values[0];
might work