Blog Font different when published

When creating a blog post this is the FONT I see when creating it:

BUT when it’s being published, It’s becoming publishing like a Garamond Font. and I have no options of changing it.

I tried typing it manually, or copy and paste it like the same font, and even clearing the formatting and type the whole thing and its still the same.

Did anyone experience this as well? Let me know how you guys fixed it.

Thanks!