Bringing old customers back

I have a database of customers who purchased glasses in my european optical shops for several years. I wonder what is the best practice to bring these customers back to my shops.

Is it a good idea to automate sending emails/texts/WhatsApp messages to them? Are there any easy to use tools for this (e.g. smth like https://www.salesforce.com/products/…ud/engagement/ but for an optical business)?

Thank you for sharing your experience.

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