compiler construction - Why Bison gives Conflict: 2 Shift Reduce error -

i'm trying below yacc grammar part gives me, wrong this? , how can solve it? there rules define grammar in bison/ yacc ?

c:\users\dilan\documents\lexprogram\miniproject>bison -dy videostore.y conflicts: 1 shift/reduce 

and yacc code :

%start videostore %token title %token type %token name %token days   %%  videostore  :   movies customers         |  customers movies           |  movies         |  customers         ;   movies      :   movies movie         |   movie         ;  movie       :   title type rentals2         ;  rentals2    :   rentals2 rental2         |   rental2         ;  rental2     :   customer1         ;   customer1   :   name days         ;  customers   :   customers customer         |   customer         ;  customer    :   name days rentals         ; rentals     :   rentals rental         |   rental         ;  rental      :   movie1         ;  movie1      :   title type         ;  %% int trace=0; 

my problem videostore.y: conflicts: 2 shift/reduce , how can wrote lex ?

use -v option bison, gives .output file showing states , conflicts are. in case, have conflicts in states 16 , 20:

state 16      7 movie: title type rentals2 .     8 rentals2: rentals2 . rental2      name  shift, , go state 15      name      [reduce using rule 7 (movie)]     $default  reduce using rule 7 (movie)      rental2    go state 24     customer1  go state 18 

this tells problem parser can't figure out end of movie rule single token of lookahead -- movie ends sequence of 1 or more rental2 rules, since rental2 begins name , things come after movie (such customer rule) start name can't tell whether should trying match more rental2s or not.

most commonly, fix using sort of delimiter @ end of rentals2 list, such ';'