I have want to do a logical check with dates.
Like the one mentioned below
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the condition I used is =IF((M6-L6)>5,"YES","NO") where M is column "Invoice received Date" and L is Invoice generated Month/date. The formula is working fine .
But for column O & M , I have a different formula =IF((O6-M6)>15,"YES","NO") where column O is having some blanks / null values also . so for such cases I want to have a different comment for such cases may be like NA or Missing Dates etc instead of "NO".
can you help me with a formula for this .
Like the one mentioned below

the condition I used is =IF((M6-L6)>5,"YES","NO") where M is column "Invoice received Date" and L is Invoice generated Month/date. The formula is working fine .
But for column O & M , I have a different formula =IF((O6-M6)>15,"YES","NO") where column O is having some blanks / null values also . so for such cases I want to have a different comment for such cases may be like NA or Missing Dates etc instead of "NO".
can you help me with a formula for this .