First DB issue

[MrBLT]

I'm trying to make a basketball database and i was going to enter each team in seperately. However whenever i enter a new team in say my score table, there is an error saying that it would create duplicate errors in the index, primary key or relationship. Why is this happening, or how can i get around this problem
Thanks

 

[Rich]

Some details of your table structure would be helpful

 

[MrBLT]

sorry about that
my table structure are as follows

gameid
date
home
away
venueid
homeATS
awayATS

gameid
1stqtr
2ndqtr
3rdqtr
4thqtr

gameid
teamid
fgm
fga
3ptm
3pta
ftm
fta
reb
foul
assist
block
steal
turnover

teamid
team

venueid
venue

this is my first database. it may be that my tables aren't right, i'm not sure.
Thanks. hope this is helpful

 

[MrBLT]

so basically i have the game info in the 1st table

gameid
date
home
away
venueid
homeATS
awayATS

i home team scores in the 2nd table

gameid
1stqtr
2ndqtr
3rdqtr
4thqtr

when i try to enter the away team scores in the same table using the same gameid, it tell me that there is an error saying that it would create duplicate errors in the index, primary key or relationship.