I have lost my passport (date of issue 2013) so that i get it new passport (date of issue 2017). recently i got my old passport it is still have a validity of 2023. will that create any problem. i need to carry both the passports
I don't know why you think you need to carry your old lost-and-found passport. Carrying it is not a problem, but chances are high that you will run into problems if you try to use it for anything meaningful.
Interpol operates a 'Stolen and Lost Travel Documents' database, to which currently 174 countries deliver data. Your old passport is probably recorded in this database. Many countries check against this database on a regular basis when verifying foreign travel documents and if you try to use your old passport at a border crossing or during an in-land id check, chances are real that a red flag is raised and that it will be an issue that you are trying to use a document, which has been reported lost.