added error and fix

README.md

@@ -1,10 +1,17 @@
 
 
 ## Multi-arch support
-- You maybe need to run this command to get buildx working properly, I do not know why.
+- You maybe need to run this command to get buildx if you get this error
+erro:
+```
+exec /bin/sh: exec format error
+```
+fixing command:
 ```bash
 docker run --rm --privileged docker/binfmt:a7996909642ee92942dcd6cff44b9b95f08dad64
 ```
+i have no idea what it does, but it seems to fix the thing ._.
+
 - You MAY also need to set these variable before running build, depending on the docker version on host
 ```bash
 export COMPOSE_DOCKER_CLI_BUILD=1