Hello @AssafL , Thanks for using Microsoft Q&A Platform.
As per my understanding, Azure bills these instances S2/D3 pricing tier on a daily basis, the monthly charge is divided by 30 and that number of units is emitted each day the resource is on that price instance.
This means that if you delete the service after a certain number of days, you will only be charged for the number of days that the service was active, based on the daily unit emission.
If you have unexpected charges Analyze unexpected charges here.
If you still face billing issues, please raise a support ticker under the Azure portal.
I hope this helps.
Regards,
Vasavi
-Please kindly accept the answer and vote 'yes' if you feel helpful to support the community, thanks.