Why r not download any application like as messenger, Facebook etc

What happens when you try? Error message(s)? Account disabled? More information would help.

If you see a message that says 'Your account has been disabled in the App Store and iTunes' - Apple Support.    

contact iTunes Support. See the Apple Support articles below for contact information.   

iTunes Support – world wide 

Apple Support schedule phone call       

If necessary, try Twitter

https://twitter.com/AppleSupport.          People have posted it may take an hour or more to get a response.

Here are some possibilities not already mentioned.

If  you can’t download or update apps on your iPhone or other Apple device https://support.apple.com/en-us/HT207165

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If you can't connect to the App Store, iTunes Store, or other Apple services https://support.apple.com/en-us/HT201400. There have been quite a few Apple server connection problems lately. Among other things, in the above document, see Check Apple’s System Status page. You can check there to see if the needed server is available when you need to use one.

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What to do when the Mac App Store shows a different Apple ID for software updates https://www.macworld.com/article/3267709/mac-app-store-apple-id.html. This document refers to a prior owner, but is also applies to cases where a current owner's old Apple ID is the problem.

Basically, If an app is purchased/downloaded using one Apple ID, then you can't update it with another Apple ID. The app is inextricably linked to the first Apple ID. You'll have to delete it and repurchase/download it again with the second Apple ID unless you use family sharing (see below).

As an alternative to deletion, you can set up family sharing between the IDs to share purchases made with them. See:

Family Sharing  https://support.apple.com/en-us/HT201060

Set up Family Sharing https://support.apple.com/en-us/HT201088