Issue editing pdf text in preview

Hi all,

I'm still very new to the mac world and all of apple's programs so please excuse me if I'm just dumb and missing an obvious fix here, but I'm having a lot of trouble editing pdfs with Preview. I'm on a macbook air running high sierra 10.13.3. The only troubleshooting I could think of to do was to restart my computer, which didn't help solve the problem.

One of the projects I'm working on requires me to edit the text in pdfs, which should be super simple except that when I click on text boxes in preview the the fill color is changed to black, font is reverted to Helvetica pt 12, and the bounds of the text box are changed. This obviously makes the text completely illegible. Interestingly enough, this only happens for text boxes that have a black border around them. I am able to change everything back to the format I want the text in, but this problem occurs every time I click a bordered text box and attempt to edit. Here are some screenshots of what has been happening to my pdfs, if it helps at all. If there's a setting or something that I'm missing that'll keep this from happening, please let me know!