doc: add a notice about the compatibility of Ingress and Dashboard (#1195)

diff --git a/README.md b/README.md
index 25189f7..afe3e0b 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,10 @@
 
 [More about comparison among multiple Ingress Controllers.](https://docs.google.com/spreadsheets/d/191WWNpjJ2za6-nbG4ZoUMXMpUK8KlCIosvQB0f-oq3k/edit?ts=5fd6c769#gid=907731238)
 
+## Works with APISIX Dashboard
+
+Currently, APISIX Ingress Controller automatically manipulates some APISIX resources, which is not very compatible with APISIX Dashboard. In addition, users should not modify resources labeled `managed-by: apisix-ingress-controllers` via APISIX Dashboard.
+
 ## Internal Architecture
 
 <img src="./docs/assets/images/apisix-ingress-controller-arch.png" alt="module" width="74.3%" height="55.9%" />