Change Font on Blackbird them – Capital T not displaying correctly

The font on my website https://www.suemazza.com is displaying incorrectly on some browsers.

The capital T ‘s look very strange and unreadable.

Can someone please tell me how to change the font across my entire site?

I’m not an expert but am generally familiar with how to edit the stylesheet, but don’t see where I can change the font for the theme.

Thank you!