From your contact dashboard, click Import.
Then, choose Import from Other Platforms and select MailerLite from the list of providers.
On the next screen, you will be asked to give MailerLite API Key, you can acquire the API key by going to MailerLite Account -> Integrations -> Developer API
Now Give your API keys and hit Next.
Now, simply map all the data(lists, tags, information) you need to import in FluentCRM and click continue.
Finally, review and Confirm!
Your all contacts with all their selected properties will be imported.