Hi @lukaszp89
First, if you want the flow to recognize the change for a specific column, you need to go to SharePoint list site, list settings> versioning settings> enable ‘create a version each time’.
If you just use the trigger ‘When an item is created or modified’ and no other limits, then flow will send you an email every time there is a change for the row with a static ‘Ready’ for the column ‘Status’.


And then, you need to add the following pictures steps: (for more information about the steps, go to the link:Check for a Change in a SharePoint List Column Val... - Power Platform Community (microsoft.com))




The schema in ‘Parse JSON’ above should be changed a little as below:
"Status": {"type": ["string","null"]}
The functions used above (which cannot be chosen from dynamic content):
body('Parse_JSON')?['d']?['results'][1]['Status']
Next, there comes to the conditions to send an email as you request.
- add the third condition (Status is equal to Ready) as below:
If yes, add the fourth condition to check if the invoice number is empty.
If no, do nothing.

- for the fourth condition (if the invoice number is empty):
If yes, delay 2 days and add the fifth condition to check if Status is equal to Ready.
If yes, add the sixth condition to check if the invoice number is empty.
If yes, send an email and add ‘do until action’ to send email every 1 day until
invoice number is filled.
If no, delay 5 days and add the eighth condition to check if Status is equal to Ready.
If yes, send an email.
If no, do nothing.
If no, do nothing.
If no, delay 5 days and add the seventh condition to check if Status is equal to Ready.
If yes, send an email.
If no, do noting.









The functions used above (which cannot be chosen as dynamic content):
empty(triggerOutputs()?['body/invoicenumber'])
empty(outputs('Get_item')?['body/invoicenumber'])
empty(outputs('Get_item_4')?['body/invoicenumber'])
div(sub(ticks(utcNow()),ticks(triggerOutputs()?['body/Created'])),86400000000000)
For the data and time functions (ticks; utcNow): Reference guide for functions in expressions - Azure Logic Apps | Microsoft Docs
For the empty function: Reference guide for functions in expressions - Azure Logic Apps | Microsoft Docs
For the math functions (div; sub): Reference guide for functions in expressions - Azure Logic Apps | Microsoft Docs
Be careful when you choose the dynamic content ‘Status’ because they’re from different ‘Get_item’ or triggeroutputs.
The whole flow is as below:

Best Regards,
Community Support Team _ Kira Xie
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