voice calls over bluetooth issue

[Android Central Question]

I am using Whatsapp on my Samsung Note 8 device. I am facing an issue that whenever I tried to make voice call through Bluetooth hands-free then call automatically goes on-hold after screen goes blank because of screen timeout. So the only solution is that I am forced to increase my screen timeout time to maximum so that screen remain ON throughout the call. I am facing this issue even when I am using wired hands free. Please help me in resolving this issue and it become very difficult to make voice calls while doing some home stuff or while driving as call goes on hold again and again and I have to keeping touching the screen so that it remain ON throughout the call