Approval fails to run when there are multiple approvers

[JoeChanUK]

Hello, I wonder if someone can help me. 

I'm trying to create an approval flow (first to respond). There will be multiple approvers. The name of the approvers are stored on a SharePoint list. 

When the flow runs, it will look up the name of the approvers based on the site they selected. 

This variable varApprovalEmail may contain one or more email addresses. The idea is that these email addresses will go into "assigned to" when starting the approval. 

What I have noticed is that if there is only one email address during the above flow process, then the flow will complete successfully with the approval request sent. However, if there are more than one addresses, the flow fails, saying 

BadRequest. The request failed. Error code: 'InvalidApprovalCreateRequestAssignedToNoValidUsers'. Error Message: 'Required field 'assignedTo' contained no valid users in the organization'.

Using the log, I noticed the field varApproverEmail only has one email address. The rest aren't visible. I can see all the details under "lookup approval email address" part of the flow though. 

What have I done wrong? 

Thanks.  

[ScottShearer]

@JoeChanUK 

I suspect the issue is that you need to add a semicolon after the email address in the Append to a string variable action.