Why has the text app' on Nougat only got letters for names now?

Before the update to Nougat a few days ago my text message list showed peoples names;now I only get a single letter.If you have three people beginning with the letter 'J' how are you meant to know which one it is?

from Android Forums at AndroidCentral.com - Ask a Question //forums.androidcentral.com/showthread.php?t=765751&goto=newpost
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