asmfiaz, Good morning.
"...Excel not recognize as date.. How can I change..."
Possibly there are some spaces in the text.
Dates may have been imported from some other system or converted from some other excel worksheet.
Try to do this:
A1 = Your date/text
C1 --> =VALUE(TRIM(A1))
Now, Try to format a cell as you desire.
Is it what you want?
I hope it helps.
Belo Horizonte, Brasil.