How to Checkif the number exist in whatsapp??

[Praveensenpai]

I tried sending message to 91234 it does send but I don't think it's valid number

I also tried sending 81818181811818181 it's sending but i don't think it's valid number

so any way to valid it first to checkif the n;umber exist in whatsapp or not before sending it???

[3mora2]

See SendMessageOptions

See all WhatsApp method