Demographics on Google Analytics

I updated Google Analytics months ago and lost all Demographic information which is extremely important for my advertisers. I’ve read about changing the tracking code to enable this feature and I’ve changed all the privacy etc. but have no idea where to find the tracking code or how to change it on my site. Help. I’ve been without this feature for so long and I don’t know what to do.

I’ve asked my web guy to help me with no luck. Please, please help.

https://www.ads-software.com/plugins/google-analytics-for-wordpress/