Why validating your contacts' numbers is important
Sending SMS to invalid numbers causes unnecessary costs. You should therefore validate your contacts' numbers regularly, and in any case before sending the first SMS.
Validating individual numbers
Basically, you can also validate individual numbers by selecting the item Number check in the left menu of the webapp and using one of the lookup variants.
Validating several or all numbers
However, since it is advisable to check all contacts regularly, as described above, you can also validate all your contacts at once. To do this, go to your contacts overview, click on More in the top right-hand corner, and then click on Validate List.
You can also validate individual groups. To do this, select the group you want to validate in the column where the groups are displayed and then click on More and Validate List.
After validation, you can see wether the number is valid in the corresponding column for each contact. A red cross means that the number is invalid, a green tickmeans that the number is valid. A yellow circle with a dash means that the recipient is absent. In this case, the destination device may not be possible to receive SMS at that moment. It is best to validate this number again at a later time.
If you wish, you can then remove the invalid numbers from your contacts by clicking More and Delete invalid numbers.
The validation costs you 0.01€ per number.