FAQs - WhatsApp (Official) - SleekFlow

More to know about Official WhatsApp Business API

Frequently Asked Questions

1. Why is my WhatsApp Message not sending?

It is usually because of the below issues:

Messaging window: You may not have opened the messaging window as you and the customer had no conversation in the last 24 hours. You need to send a template message to reopen the messaging window to respond to the customers. You can check more details about messaging window here.

Message Format: The template message you sent may not be in the registered templates' right format. Please check again with your template on the platform or submit new templates for WhatsApp to review. For more information about template messages, please check this guide.

2. Do I have to pay separately for both the SleekFlow plan and the Official WhatsApp plan?

Yes, the bill has to be separate from your SleekFlow account. For example, you subscribe to Pro Plan and connect to Official WhatsApp Business API. You need to pay for the SleekFlow Pro Plan price and the Official WhatsApp Business API pay-as-you-go fee.

3. What is the pricing for Official WhatsApp Business API?

360dialog charges WhatsApp Messages on a pay-as-you-go basis. Each country has different messaging pricing for templated and session messages. For more information, please check this link and search for your countries.

4. Is there any limits on how many messages each WhatsApp number can send?

Yes! WhatsApp has imposed rate-limiting when ramping up your Official WhatsApp messaging application for these approved and enabled customers. (1000 unique recipients/ day when you start)

Please refer to the guide below to learn more.

pageMessaging Limits

5. What are the extension and limitations of the Official WhatsApp API?

Connection is important - now more than ever!

The Official WhatsApp API empowers businesses to connect with customers at scale with broadcast messages, automation and the like. With the Official WhatsApp API, you can start conversations with multiple customers with personalized messages!

Having said that, the Official WhatsApp API does not support WhatsApp calls and group chats at the moment. Furthermore, contacts would not be able to invite the Official WhatsApp number to the group chat as well.

6. Are there any guidelines for sending and receiving attachments on the Official WhatsApp API?

The Official WhatsApp API supports sending and receiving documents, images, audio and video. For more info, visit here.

MediaSupported Content TypesFile ExtensionsSize Restriction


Currently restricted to PDF and Office documents

.pdf, .do*, .xl, .ppt, .sx*, .od*

100 MB


image/jpeg, image/png

.jpeg, .jpg, *.png

5 MB


audio/acc, audio/mp4, audio/amr, audio/mpeg, audio/ogg; codecs=opus

.acc, .mp4, .mp4a, .amr, .mpeg, .ogg

16 MB


video/mp4, video/3gpp

*NOTE: All video files will need an audio track. Otherwise the file won't be delivered.

.mp4, .3gp, *.3g2





Static stickers: 100KB

Animated stickers: 500KB

The Official WhatsApp API does not support sending and receiving location and contact details (VCF file) at the moment. However, users are able to send and receive contact details real soon, stay tuned for the upcoming feature!

6. How many phone numbers can I add to my WABA account?

By default, you can only add 2 phone numbers to each WABA account. This is a fraud prevention feature.

While you can add more than 2 phone numbers to a WABA account when your Facebook Business account is verified. If you want to add more than 2 numbers, please contact our Customer Support for further assistance.

7. I wasn't able to send my message. Could you advise me on how to check the error code that was shown?

You can refer to this documentation for the description and possible solutions.

Common error codes:

CodeDescriptionPossible Solutions


Something went wrong

Message failed to send due to an unknown error.

Please try again.


Recipient cannot be sender

Sender and recipient phone number is the same.

Send a message to a phone number different from the sender.


Message Undeliverable

Unable to deliver message. Reasons can include:

  • The recipient phone number is not a WhatsApp phone number.

  • Recipient has not accepted our new Terms of Service and Privacy Policy.

  • Recipient using an old WhatsApp version

Confirm with the recipient that they agree to be contacted by you over WhatsApp and are using the latest version of WhatsApp.


Re-engagement message

More than 24 hours have passed since the recipient last replied to the sender number.

Send the recipient a business-initiated message using a message template instead.

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