JSFiddle - React, Tailwind, and code Playground

HTML

<input type= "text" id="inn"></input>

CSS

input {
    
    margin-left:30px;
    margin-top:50px;
}

JavaScript

document.addEventListener('keypress', function(event) {
  
   var input = (document.getElementById("inn").value); 
   
    if(input.length > 1)
    {
        var enteredValue = String.fromCharCode(event.keyCode);
        var lastEnteredValue = input.substr(-1, 1);
        var lastBeforeValue = input.substr(-2, 1);

        if(enteredValue== lastEnteredValue && enteredValue == lastBeforeValue)
        {
          event.preventDefault();          
        }
        
        
    }
    
}, true);