If you are unable to book train tickets through your IRCTC account, there could be a few reasons for this. Here are some possible solutions:

1. Check your internet connection: Make sure that you have a stable internet connection before attempting to book train tickets. A slow or unstable internet connection can cause issues while booking tickets.
2. Clear your browser cache: Sometimes, your browser cache may cause issues while booking train tickets. Try clearing your browser cache and cookies, and then try booking tickets again.
3. Check for website updates: It is possible that the IRCTC website is undergoing maintenance or updates, which may cause issues while booking train tickets. Check for any updates on the IRCTC website or try booking tickets at a later time.
4. Check your account balance: Make sure that you have sufficient balance in your IRCTC account to book the train tickets. If you do not have sufficient balance, you will not be able to book the tickets.
5. Try a different browser: If you are still unable to book tickets, try using a different browser to access the IRCTC website.
6. Contact IRCTC customer care: If none of the above solutions work, you can contact IRCTC customer care for assistance. They can help you troubleshoot the issue and guide you on how to book train tickets.

It is important to note that booking train tickets through IRCTC is subject to certain terms and conditions, and may not be available for all users. Make sure to read the terms and conditions before booking train tickets through IRCTC.