Gmail应用程序在Vivo Android Mobile中没有区分读取和未读电子邮件 -- gmail 领域 android 相关 的问题

In Android Gmail App, It has unread emails with bold and read emails without bold to identify which emails are unread. But in my Vivo V7 Android Mobile I couldn't able to see that differentiations and all the emails are showing without bold and hence this app is not so helpful for me.

Below are the steps I tried,

1. Cleared Cache of App.
2. Signed out and Signed in
3. Rebooting mobile
4. Tried al the settings

Nothing helped me. Please give a solution for this issue,

As mentioned by Robert and Andrew in comments, this issue was due to System Font, which was a custom one and not a default one. Once I changed to Default Font, I could able to see gmail is showing as normal fonts.