Failed to delete default.mysql5.7: Default DBParameterGroup cannot be deleted:

[gstripura]

Failed to delete default.mysql5.7: Default DBParameterGroup cannot be deleted: default.mysql5.7 (Service: AmazonRDS; Status Code: 400; Error Code: InvalidDBParameterGroupState; Request ID: b18d92d2-83e0-4700-9621-9407fe06dc64).

[gstripura]

There is Option Groups created with Default option group for mysql 5.7 | MySQL Community
has a disabled delete button as shown in the snippet , this also cannot be deleted.