Lcd display. One by one each phone has developed an unreadable screen, making it useless for

Question

One by one each phone has developed an unreadable screen, making it useless for caller ID or reading the display.  I bought a 3-phone set about a year ago, and each phone in turn went foggy until now all three are worthless for anything except calling or getting call, which is only part of the service In pay for.

Daniel Krueger
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