Delete all indices

Hello all, we are using amazon opensearch 1.2.
We use OpenSearch 1.2 from Amazon as a service. We wanted to test restoring a snapshot. To do this, the indices must first be deleted. When I use the following command delete /* I get the following error message:
“error” : {
“root_cause” : [
“type” : “security_exception”,
“reason”: “no permissions for and User [name=ar, backend_roles=[opensearch_admin, kibana], requestedTenant=]"
“type” : “security_exception”,
“reason”: "no permissions for [] and User [name=a
r, backend_roles=[cinnamon_prod_opensearch_admin, kibana], requestedTenant=]”
“status” : 403

I definitely have admin rights.
I am assuming that certain indices should not be deleted.

How can I solve this problem?