The problem is doing either FT.SEARCH or FT.AGGREGATE command on an index that contains 15999 documents and asking for an offset beyond 10000.
redis-cli output...
127.0.0.1:6380> FT.AGGREGATE rentals:default:idx:rentallisting:default @type:{_invalid|condo|apartment|bachelor|basement|studio|duplex|loft|house|town_house|multi_unit|cabin|cottage|room|private_room|shared_room} LOAD 1 @__key APPLY "@highlight_status_value * 100" AS rank SORTBY 4 @rank DESC @modified DESC LIMIT 9999 1
1) (integer) 15599
2) 1) "__key"
2) "rentals:default:doc:rentallisting:item:cmVudGFsbGlzdGluZzo1NjExNDY="
3) "highlight_status_value"