Ubidots delivery does not handle the same variabile with multiple timestamps

Something like

```
"timeseries": [
   { "name": "x": "timestamp": "2025-09-09T01:01:01Z", "value": 1.0 },
   { "name": "x": "timestamp": "2025-09-09T02:01:01Z", "value": 1.5 }
]
```

Does not work because the variable name is being used as a key in a dictionary so one entry overwrites another.
