Does your employer have to tell you if they make changes to your health insurance?

So I found our new insurance cards in the mail and noticed our copay went from $20 to $25. I'm wondering what else changed on our insurance without being told about it. Can your employer legally make changes like that without telling you? I'm wondering if our deductible is still the same.
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No, they don't. Absolutely, they can make changes without telling you - or they can cancel the coverage without telling you, too. You'll have to ask someone, if the deductible is the same.
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