[Python] Matching rule of antlr regex

Im working on a lexer of a school project, using antlr4. The string literals of the language defined like this: grammar MiniGo;

@lexer::header {
from lexererr import *
}

@lexer::members {
def emit(self):
tk = self.type
if tk == self.UNCLOSE_STRING:
result = super().emit();
raise UncloseString(result.text[1:]);
elif tk == self.ILLEGAL_ESCAPE:
result = super().emit();
raise IllegalEscape(result.text[1:]);
elif tk == self.ERROR_CHAR:
result = super().emit();
raise ErrorToken(result.text);
else:
return super().emit();
}

options{
language=Python3;
}

program : decl+ EOF ;

decl: funcdecl | vardecl ;

vardecl: 'var' ID 'int' ';' ;

NL: '\n' -> skip; //skip newlines
WS : [ \t\r]+ -> skip ; // skip spaces, tabs

funcdecl: 'func' ID '(' ')' '{' '}' ';' ;
// identifiers
ID: [a-zA-Z_] [a-zA-Z0-9_]*;

// String literals
ESC: '\\' [ntr"\\];
STRLIT: '"' (~["\\] | ESC)* '"';

// Exceptions
ERROR_CHAR: .;
ILLEGAL_ESCAPE: '"' (~["\\])* ('\\' ~["\\rnt]);
UNCLOSE_STRING: '"' (~["\\] | ESC)* ('\n' | '\r' | EOF);


When i go an input like hello\. It matches the STRLIT, not the UNCLOSED_STRING one. But I can't understand why it can match the STRLIT? If it matches by the \ character, it cannot match the last ". But it also can't match the last " as the close quote because i dont allows \ stand alone in the input as well. Can someone explain this to me? May be i missed something in the antlr matching rules?

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