TypeError: Cannot read properties of null (reading 'value'

[Teslimat]

When I tried console.log(quantity)
I received the error message "TypeError: Cannot read properties of null (reading 'value')
at HTMLButtonElement. (amazon.js:75:46)"

[Teslimat]

Here is a screenshot of my js code. Kindly assist

[Schemper]

Hi Teslim, according to the error in your message, the problem appears to be on line 75. The correct code should be:

const quantity = Number(quantitySelector.value)

The difference here is, the value gotten from the quantity selector is converted to number from string. You can check this out.
P.S. I am still learning so I might be way off but I was able to check compare my code with yours and since I am a little bit ahead and thought to help.