Notetweet works fine but the scheduler is not working

[Polonco]

I installed the scheduler on Heroku (free plan) and configured the scheduler in Obsidian following the instructions.

Step 1

Step 2
I click schedule

Step 3
I click enter

Step 4
I'm back to this

If I click on Scheduled Tweets I just see a blank popup

I watched the demo video multiple times but the behavior I experience is different from the one in the tutorial.

I can tweet without any problem but I can't schedule the tweets.

Did I miss something? Thanks in advance!

I'm using
Windows 10 Enterprise
Obsidian 0.15.9
Notetweet 0.4.3

[Polonco]

After installing the Natural Language Dates plugin https://github.com/argenos/nldates-obsidian it is working as expected.
I suggest to highlight better in the documentation that the plugin must be installed separately because the wording used now is misleading.