MYSQL Error Code 1452

Error Code: 1452. Cannot add or update a child row: a foreign key constraint fails (`sys`.`matches`, CONSTRAINT `MATCHES_FK1` FOREIGN KEY (`FIRSTTEAM`) REFERENCES `team` (`teamid`))

3 CREATE TABLE MATCHES ( MATCHID CHAR(5) NOT NULL, FRSTTEAM CHAR(4) NOT NULL, SECONDTEAM CHAR(4) NOT NULL, MATCHDATE DATE, KICKOFF TIME, STADIUMID CHAR(3) NOT NULL CONSTRAINT MATCHES_PK PRIMARY KEY (MATCHID), CONSTRAINT MATCHES_FK1 FOREIGN KEY (FIRSTTEAM) REFERENCES TEAM (TEAMID), CONSTRAINT MATCHES_FK2 FOREIGN KEY (SECONDTEAM) REFERENCES TEAM (TEAMID CONSTRAINT MATCHES_FK3 FOREIGN KEY (STADIUMID) REFERENCES STADIUM (STADIUMID)