It does that because that is what you asked the code to do. To only get it to print once you have to remember what the button state was and then only print if it is now different from the last time you read it.
Use a variable called lastTime, the last thing in your loop() do:-
lastTime = BUTTON1;
then in the if statement :-
if ( ( buttonValue1 == HIGH) && (latsTime==LOW ) ) {
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