Speed test cli

I have a bash file


    #!/bin/bash
    (date) >> ~/log/speed.log
    speedtest-cli >> ~/log/speed.log


When I run it from the commandline like sh speed.sh, 
it works just fine. 
When I run it as a crontab,
I only get the date, 
not the speed test results. 

Why is that? 

tags: question, tech-support, bash, fedora-31, speedtest-cli, automation