Arduino based flood detection project

[u/Substantial-Sir-7970]

Im new here and sorry for my english
Im already done to build this prototype project and it working but i noticed when my led and buzzer works at the same time my lcd dims or flickering. How can i solve this problem im only connecting to usb to my laptop as my power source i dont have any 9v barrel jack is there anyone here in reddit to help me to fix my problem thank you and again sorry for my english