docs(messaging): documentation for dead letter queue limits

Author: Dina ABAKKALI

identity-and-access-management/organizations-and-projects/additional-content/organization-quotas.mdx

@@ -283,7 +283,10 @@ Note that in memory stream are not supported, please create your NATS stream usi
 
 ## Queues
 
-Scaleway Queues is a product for creating managed messaging queues based on the [SQS](/serverless/messaging/concepts/#nats) protocol. The following usage limits are enforced as Organization quotas when using Scaleway NATS:
+Scaleway Queues is a product for creating managed messaging queues based on the [SQS](/serverless/messaging/concepts/#nats) protocol.
+A dead letter queue ([DLQ](/serverless/messaging/concepts/#dead-letter-queue)) is a type of queue, and all the limits that apply to regular queues also apply to DLQs.
+The following usage limits are enforced as Organization quotas when using Scaleway NATS:
+
 
 | Resource                                       | Criteria   | Limits   | Scope            |
 |------------------------------------------------|------------|----------|------------------|

serverless/messaging/concepts.mdx

@@ -27,7 +27,7 @@ Credentials give services and platforms access to Scaleway NATS, Queues, and Top
 
 ## Dead Letter Queue
 
-A **D**ead **L**etter **Q**ueue (DLQ), or **undelivered-message queue**, receives and holds messages that cannot be delivered to their destination queues. This concept is not yet implemented for Scaleway Queues.
+A **D**ead **L**etter **Q**ueue (DLQ), or **undelivered-message queue**, receives and holds messages that cannot be delivered to their destination queues. If you use the dead letter queue, and the storage quota is reached, messages won't be redriven to the DLQ until enough free space is available again. If you get in a situation where the quota is reached, you need to make some free space by receiving and deleting messages from any queue of your project.
 
 ## Fanout