DatedDiff formula is not calculating correct consistently

[jhoyabel19]

Hi PBI Newbie here!

Need help tried the DatedDiff formula to get the day difference between two dates but the formula is not calculating correct. I dont know what seems wrong. Hope you can help me.

TTOB = DATEDIFF('App Dur Apply'[OfferDates],'App Dur Apply'[HiredDates],DAY)

Values of offer dates and hired dates were looked up from different table

Relationship is 

[v-yiruan-msft · Accepted solution]

Hi @jhoyabel19 ,

It seems that the data type of the field [OfferDates] and [HiredDates] in the table 'App Dur Apply' be set as Text type, please change their data type as Date. Then you can get the correct result... You can find the details in the attachment.

Best Regards