QB Issue Resolution:

Export your contact list from contacts app in a csv format, then import into QBO using import function on customer screen, you’ll have to make sure you have the columns correctly mapped which may need a bit of concatenating in Excel.

Resolution for Issue 'I’m new to quickbooks and I run a mac. How do I import my customer details from my contacts.' available: Yes (Solved).
Source: Intuit Community forum.

I’m new to quickbooks and I run a mac. How do I import my customer details from my contacts.: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for columns correctly
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Error Recovery for columns correctly [Canada]
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