Why doesn't want to parse string(Regex)?

Question

.NET

There is a line like
\nWIKI/NYRT,\"New York REIT Inc (NYRT) Prices, Dividends, Splits and Trading Volume\"\nWIKI/OPWR,\"Opower Inc (OPWR) Prices, Dividends, Splits and Trading Volume\"\ n
I use a regular expression with a pattern

string pattern = "/(.*?)[\\/]([A-Z]*)(,.)(\".*?\")/gm";
Regex regex = new Regex(pattern);

On Regex101.com everything works fine
In the code for some reason there is no
problem What is the problem?

Answer 1

string pattern = " / (.*?)[\\/]([AZ]*)( ,. )(\".*?\") /gm ";

string pattern = "(.*?)/([A-Z]*)(,|.)(\".*?\")";
var regex = new Regex(pattern, RegexOptions.Multiline);