RQG: min query giving wrong result on IndexScan

Query which gives wrong result:

SELECT min( decimal_field1 ) FROM simple_table_1 WHERE NOT ((decimal_field1 < 5024) OR (decimal_field1 <= 5024)) ;

Result:
[

{ "$1": null }

]

Explain of above query:
[
{
"plan": {
"#operator": "Sequence",
"~children": [
{
"#operator": "IndexScan",
"covers": [
"cover ((`simple_table_1`.`decimal_field1`))",
"cover ((meta(`simple_table_1`).`id`))"
],
"index": "simple_table_1_idx_decimal_field1",
"index_id": "fb8e662572c5708b",
"keyspace": "simple_table_1",
"limit": "1",
"namespace": "default",
"spans": [
{
"Range":

{ "Inclusion": 1, "Low": [ "5024" ] }

}
],
"using": "gsi"
},
{
"#operator": "Parallel",
"maxParallelism": 1,
"~child": {
"#operator": "Sequence",
"~children": [

{ "#operator": "Filter", "condition": "(not ((cover ((`simple_table_1`.`decimal_field1`)) < 5024) or (cover ((`simple_table_1`.`decimal_field1`)) <= 5024)))" }

,

{ "#operator": "InitialGroup", "aggregates": [ "min(cover ((`simple_table_1`.`decimal_field1`)))" ], "group_keys": [] }

]
}
},

{ "#operator": "IntermediateGroup", "aggregates": [ "min(cover ((`simple_table_1`.`decimal_field1`)))" ], "group_keys": [] }

,

{ "#operator": "FinalGroup", "aggregates": [ "min(cover ((`simple_table_1`.`decimal_field1`)))" ], "group_keys": [] }

,
{
"#operator": "Parallel",
"maxParallelism": 1,
"~child": {
"#operator": "Sequence",
"~children": [
{
"#operator": "InitialProject",
"result_terms": [

{ "expr": "min(cover ((`simple_table_1`.`decimal_field1`)))" }

]
},

{ "#operator": "FinalProject" }

]
}
}
]
},
"text": "SELECT min( decimal_field1 ) FROM simple_table_1 WHERE NOT ((decimal_field1 < 5024) OR (decimal_field1 <= 5024)) ;"
}
]

Index used:
CREATE INDEX `simple_table_1_idx_decimal_field1` ON `simple_table_1`(`decimal_field1`) WITH

{ "defer_build"=true }

Same query with primary index gives correct result:
SELECT min( decimal_field1 ) FROM simple_table_1 use index(`#primary`) WHERE NOT ((decimal_field1 < 5024) OR (decimal_field1 <= 5024)) ;

Result:
[

{ "$1": 5028 }

]

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