X-Influxdb-Error: unable to parse 'dht22, t=22.22 h=50.90 hic=20.04': missing tag key

Folks,
I am trying to inset a point of DHT22 values with
curl -i -XPOST ‘http://192.168.1.117:8086/write?db=IOT&u=root&p=123456’ --data-binary ‘dht22, t=22.22 h=50.90 hic=20.04’

But what I got is
HTTP/1.1 400 Bad Request
Content-Type: application/json
Request-Id: 04b85a2c-2c39-11e8-ac5e-000000000000
X-Influxdb-Build: OSS
X-Influxdb-Error: unable to parse ‘dht22, t=22.22 h=50.90 hic=20.04’: missing tag key
X-Influxdb-Version: 1.5.0
X-Request-Id: 04b85a2c-2c39-11e8-ac5e-000000000000
Date: Tue, 20 Mar 2018 12:20:03 GMT
Content-Length: 80

{“error”:“unable to parse ‘dht22, t=22.22 h=50.90 hic=20.04’: missing tag key”}

I thougth the tag keys are optional. what am I missing here?

No space after the comma, no spaces between fields. InfluxDB Line Protocol tutorial | InfluxDB OSS 1.5 Documentation

dht22,t=22.22 h=50.90,hic=20.04