A number was provided that cannot be a real phone number due to wrong format or is ambiguous e.g. because no country prefix was provided and the number itself could belong to several countries.
- +5456545451515544 - too long
- 5464654 - country prefix not provided - will only work if the default prefix from user settings fits
- +31fgf6464w54 - contains letters
An inactive number is a valid phone number, which is permanently or temporary not active and cannot receive SMS or calls.
- Phone is switched off
- Phone has no reception
- Phone was cancelled/deactivated by the MNO