How do I deal with Tab + new line chars in Antlr?

Hello everyone,

I'm having some trouble dealing with a tab character comes before a new line character. 

The image below (the second line of the image) exemplifies what I'm talking about:

-----> FAIL

-------> OK

The grammar I've made doesn't consider TAB + NL the same way that just using NL.

The section that I define the rules for white spaces and new lines is the following:

WS : (' ' | '\t' | '\f')+ {$channel = HIDDEN;};
NL : ('\n' | '\r')+ ;

Any hint on that? I've tried already '\t\n', '\t\r'.

thanks