Reach out to your customers, try to automate this process.
if you have a customer database setup that’s very good, else you need to start making customer database with contact details, as this helps you to communicate with your customers and get a personalized engagement channel.
make note of who all have come up and purchased and see who has not then shoot up sms/ email/ Whatsapp message and keep them informed about your business timings, offers, promotions, and keep in touch.
(you can visit this link, where you can find what messages to send during and post COVID – https://datafussion.com/news_event/how-to-keep-communicating-with-your-customers-during-covid-19-corona-virus/)