I understand your problem: You need a Make scenario to run at the exact date and time specified in your Monday.com column. These will be at different times of the day. The problem is that Monday.com will only trigger an automation on the day and not at the time specified in the column.
You could have Make poll for this column every Minute, but I assume you thought of that but this would use too many operations.
My approach would be to approach it slightly differently. Instead of having a Webhook triggered when the time arrives, instead, schedule the Make scenario to run at that exact time. It is a little complicated, but if this is a critical function, then please bear with me.
1. Create a Trigger Scenario
Create a scenario with a single module that will trigger your actual scenario (the “Trigger scenario”). You could use an HTTP module to trigger the scenario’s webhook or the Make module to “Run a scenario”. Save the blueprint of this scenario. This scenario will be copied over and over again, once for each time you want your automation to run.
2. Create a Scheduling scenario
Create a second scenario that will schedule your first scenario to run (the “Schedule scenario”). It will need a webhook to receive information about the row and the date and time from Monday.com. Then use the Make “Create a scenario” module to create a copy of your Trigger scenario, and specify the exact date you want the scenario to run in the Scheduling fields.
3. Activate the Scheduling scenario from Monday.com
Now, use the “When Column changes” automation in Monday.com to send the date and time to the Scheduling scenario. This will create a new copy of the scenario to run on the date and time you specified. This could be days, weeks or months in advance.
It will need a bit of tweaking. You’ll want to build a mechanism to handle deleting scheduled Trigger scenarios if the Date and Time in your Monday.com column changes. You’ll also need to delete the Triggering scenarios once they have run, but that can also all be automated.
…but it is one way to do what you want it to!