Blogs Displaying HTML

I’m hoping someone can help me – I’m having an awful day. I’ll try to explain as best I can.

I’m using the Tesseract theme with Beaver Builder (Reading settings show the Front Page as Home and nothing is set as the Posts page).

Up until yesterday my Blog page and posts were fine. My Blog page showed featured images and excerps, and recent posts, etc were displayed on the right.

My blog posts started displaying html yesterday. If I view individual posts (via WordPress, no html is showing.)

All of my posts were set to Full Width Page when I created them and, up until yesterday, this is how they displayed. However, now a left sidebar is showing.

I’ve deleted the Blog page and created a new one but when I add the blog module (that comes with the theme), blogs are not compact and html is showing. This also happens if I don’t use Beaver Builder and set the Reading settings Posts page as the Blog page.

I’ve spent all day trying to fix this and I’m absolutely demented. My web host had problems yesterday and my site was down quite a lot. I’ve asked them if this could have caused the problem but they’re adamant that it hasn’t. They suggested that I look at the scripts but I have absolutely no idea how to do that.

Can anyone help please?