Hi preeti-agarwal, 

The error you receive when importing Trial Balances is an ongoing investigation, and we haven't received any updates yet. Rest assured that our engineers are currently investigating and working on an immediate fix. I suggest reaching out to our Phone Support Team so they can add your account to the list of affected users. 

Once fixed, you can check out this link on how to import trial balances. 

Thanks for your patience while we're working on a permanent fix. I'm just here if you have other questions. Take care!