Meta description not showing correcty

please help. I just want to use the SEO yoast plugin however it keeps showing this.
Your theme contains a meta description, which blocks WordPress SEO from working properly, please delete the following line, or press fix it:
<meta name=”description” content=”Look and feel better everyday with our personal diet plans tailored to your taste and health requirements.”>

It wont fix it.
I’ve deleted it on pages. It’s still showing this.
please speak English. I don’t understand what php means. I just wan’t to fix this.
Simple for you guys but very difficult for me.