I am following the instructions to merge duplicate accounts in Chart of Accounts but when I get to 'Save' there is no option to merge, just a message to say the account name is a duplicate.

I appreciate you following the instructions in merging duplicate accounts to keep your lists clean, @JE36. Let me provide insights to help you complete the task in QuickBooks Online (QBO).

The message indicating that the account name is a duplicate without the option to merge could be due to Account and Detail Type mismatch.

When you merge duplicate accounts, their Account and Detail Type should also be the same aside from their name. If the detail types are distinct, QuickBooks will not provide the option to merge. 

Refer to this article for more details: Merge duplicate accounts in QuickBooks Online. Reviewing each of these aspects can help identify the reason. 

However, if all details are the same for both accounts, change the name of one account to something different. Here's how:

1. From the Cog Wheel, click Chart of Accounts.
2. Open the 1st duplicate account where you receive the error message.
3. From there, change the name into something different. Example: Sample Account to Sample Accounts
   
   
    
4. Save your changes.

Reopen it by clicking Edit from the dropdown. Then, change the name back to the original the same as the duplicate. This time, when you click Save, it'll give you the option to merge accounts. See the screenshot below for a visual reference.

Moreover, it's important to reconcile your accounts every month so they always match your bank and credit card statements. This way, we can ensure the accuracy of your books.

I'll be in the community space if you have more questions regarding your QuickBooks accounts. Leave a reply below and I'll be sure to help you.