My grandma has a new Huawei phone that has an odd configuration. Whenever she adds a new contact, it doesn't appear in the phonebook, but in Viber instead. Naturally when she goes to her phonebook looking for her friends and doesn't find them, even though she had added them earlier, she gets very frustrated.
Since she's pretty old, I can't expect her to figure it out on her own. Is there a way to fix this? Viber hijacking your phonebook and not letting you add any contacts is pretty annoying.