Oracle 21c

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create table customer (cif number, name varchar(20),mobile number);
begin
insert into customer values(121,'ANT',789);    
insert into customer values(122,'ANT',789);   
insert into customer values(123,'ENT',789);    
insert into customer values(124,'ENT',789);    
insert into customer values(125,'BEE',123);    
insert into customer values(126,'BEE',123);    
insert into customer values(127,'BRO',789);    
insert into customer values(128,'FIO',789);    
end;
/
1 rows affected

SELECT cif, name, mobile
  FROM (SELECT c.*,
               COUNT(*) OVER (PARTITION BY name, mobile) AS cnt
          FROM customer c )
 WHERE cnt > 1  


CIF
NAME
MOBILE


122
ANT
789

121
ANT
789

126
BEE
123

125
BEE
123

123
ENT
789

124
ENT
789