Few companies data not available after importing to database

I am using Amibroker 6.20.1

When new stock comes to the market and data of which (o,h,l,c,v) becomes available, I usually import it to my Database Folder.

Recently i found that few new stocks data are not available to my database.

For example, 5 new companies comes to the market and their data are available and of which 3 companies data available to my database after importing all companies data (including those 5) to my database.
Unfortunately 2 companies data are not available though i have imported all companies including these 2.

One thing to be noted that i usually import data using 'import ascii' wizard (a format is saved and I used that to import data from long ago)

However, if i use 'import wizard' those 5 new companies data including previous 2 become available to my database and if i save the database with these two new companies and exit the program and subsequently open the program, again that 2 companies data becomes unavailable.

It is happening for the specific two stocks whose data is available for more than 2 months but not showing in my database.

what can be cause of the problem?

Expert opinion pls.