Returned matched.edge_index are all zeros

I'm currently using Valhalla 3.1.4 to map-match the gps data, but the **matched.edge_index** only returned zeros for almost all the points except the last point(which returns the final edge_index)

An example request to generate the bug:
[example.csv](https://github.com/valhalla/valhalla/files/7783499/example.csv)
"use_timestamps": True,
"begin_time": begin_time_str,
"durations": durations,
"shape": shape,
"costing": "auto",
"shape_match": "map_snap"

Matched results:
In csv:
[matched_result.csv](https://github.com/valhalla/valhalla/files/7783502/matched_result.csv)
In json:
...
[{'distance_from_trace_point': 2.668,
'edge_index': 0,
'type': 'matched',
'time': 214,
'distance_along_edge': 0.354,
'lat': 13.663338,
'lon': 100.503022},
{'distance_from_trace_point': 2.668,
'edge_index': 0,
'type': 'interpolated',
'time': 214,
'distance_along_edge': 0.354,
'lat': 13.663338,
'lon': 100.503022},
{'distance_from_trace_point': 3.175,
'edge_index': 0,
'type': 'matched',
'time': 225,
'distance_along_edge': 0.562,
'lat': 13.662288,
'lon': 100.50258},
{'distance_from_trace_point': 3.175,
'edge_index': 0,
'type': 'interpolated',
'time': 225,
'distance_along_edge': 0.562,
'lat': 13.662288,
'lon': 100.50258},
{'distance_from_trace_point': 6.381,
'edge_index': 34,
'type': 'matched',
'time': 234,
'distance_along_edge': 0.225,
'lat': 13.661333,
'lon': 100.502142}]