Apple mail OS 10.15 Type size changes but font won't change in message viewer

I just upgraded my MacBook Pro from 10.14 to 10.15.7. Probably one of the easiest upgrades I can remember. Now the only issue is the Message list font won't change. The type size changes, but not the font. The font is changed in messages. It seems just the message list isn't.

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I'm trying to change the message list font to Times New Roman 18. The font is not changing in the message viewer list. This only happened after the upgrade.