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Sounds like it's your account settings and not the sim, I can't see how a sim could only affect one app anyway.
Have you worked through the following: https://faq.whatsapp.com/en/android/20887936/?category=5245260 or https://faq.whatsapp.com/en/iphone/20950116/?category=5245260 depending on phone.
I might add that Whatsapp works on mine as intended.