SELECT statement brings records with empty measures in AWS Timestream table

Hello: I have a MULTI measure table in AWS Timestream, and when I run a SELECT to bring values from a measurement, it brings rows including those where the measurement does not exist. For example, having measures like 'temp' and 'humidity', the following query:

SELECT temp, time FROM "test"."reports" WHERE  time between ago(1d) and now() ORDER BY time DESC LIMIT 100 

brings these records:

temp       time
21.55	2022-08-27 00:02:43.478000000
-       2022-08-26 23:35:11.490000000
23.2	2022-08-26 23:34:36.090000000
24.1	2022-08-26 23:34:17.332000000
24.1	2022-08-26 23:31:09.975000000
24.1	2022-08-26 23:29:56.867000000

So my question is why the record without 'temp' data is returned by the SELECT statement? How should I filter out this value?

Thanks