Hi,
This could be related to this issue: https://github.com/elastic/kibana/issues/24628.
Do you by any chance have more than 20 index patterns? You can see that by going to this url: <kibana-host-url>/api/saved_objects/_find?type=index-pattern
You should get a response like:
{
"page": 1,
"per_page": 20,
"total": 5,
"saved_objects": [...]
}
The number in total indicates the number of index patterns.