Whatsapp messages show double tick but not delivered

That seems to be an issue with the internet connectivity of either of you. When you say the message you sent shows double ticks, what timestamp does it show?If it is proper then it could be an issue with the internet connection of the receiver.

Essentially, WhatsApp will need continuous connectivity for the messages to be delivered instantly. If the receiver has set Restrict Background Data for either WhatsApp or Google Services., the messages are bound to be delayed and offer different timestamp.

Task killers too can cause delay in sending and receiving messages. If you or your recipient has any such task killers installed, it is advised to uninstall them and check.

Another solution could be to log out from WhatsApp On WebMenu Button > WhatsApp Web > Logout from all computers.

Does this happen only with a particular recipient, or all of them? If this issue is with just a couple of recipients and works fine with others, it is definitely an issue with the recipient's phone or internet connection. If everything fails, I would advice you to uninstall and reinstall your WhatsApp. Make sure you take a backup of chats before doing so.

Let me explain you the delivery mechanism of Whatsapp so that you understand what is going on here.

WhatsApp works on XMPP protocol that stands for (eXtensible Messaging and Presence Protocol) that allows you to send quicker text messages compared to messengers using TCP/IP protocols. WhatsApp doesn't host content on their own server if both the users are online. So no amount of data that we send gets hosted while both users are synced online. Even the encrypted content happens on the App level and only delivery process is passed through their server.

Does that mean data is never stored? No exactly. Storage only happens when source and destination goes offline alternatively. Also, In some file format cases the data is supposed to be stored on their servers for packet verification. Also in case of the source being offline and then data is being sent from the Whatsapp server in his/her absence to make the message reach the destination. In such case the data is stored on their server.

When you send messages to another user. The ticket and time stamp is generated on the WhatsApp server. If the user is available online then your content goes through severs validation process and sends you confirmation using single tick for server entry, two ticks for messages packet sent, and two blue ticks for receptions verification.

If you are sending the data and you get two gray ticks from your end, and user is not online, in such case the data is still registered with time stamp and packet on server. Once the user gets online then the server uploads the content to users app.

If you are sending the content while being online and user is not online, and he's not getting the content when he comes online, then there is issue with the WhatsApp delivery mechanism. If you are sending the content while both you and another user being online and data is not being received then also there is issue with Whatsapp. And if you are sending the data and user is not online but you're getting two gray ticks and user comes online and gets the data and your timestamp status updates then there is no issue.

Timestamp updates happen dependent on the receptions capacity to receive the update. So you may send update today and if user turns on the device after 2 days then the timestamp will reflect that specific time when the delivery happened on the device.

Just check it if its happens with only one contact or all the contacts. If only one contact then delete the contact and add it. Now check that. If it happens with all the contacts. Then try to disable the app ( Go to settings-- Apps--Whatsapp--Disable ) from settings and open the app. If the issues isn't solved then uninstall the app by deleting whole data ( Both cache & normal ) then re install it and add all the details.

Check out if you are using whatsapp web then delete it from whatsapp and repeat the same from the mobile.