Every marketing email and every customer page has a way to opt out.
What the customer sees
The link opens a page, Stop reminders from (your business)? It says they won't get service reminders or offers, and that messages about a job they book will still reach them. They press Unsubscribe, then see You're unsubscribed.
Customers can also turn reminders on or off from their own customer page, using Stop reminders and Send me reminders.
What you see
On Customers, their Reminders column changes from Opted in to Unsubscribed. They are left out of every campaign and reminder from then on.
What still reaches them
Messages about a job they've booked: confirmations, estimates, invoices, receipts. These are not marketing.
Texts
If a customer replies STOP to a text, texts to them are off. See When a customer texts STOP or HELP. If you open their request, Zome says "They texted STOP, so texts to them are blocked. Call them instead."
Don't re-add them
Don't tick the "agreed" box for someone who unsubscribed, and don't import them back as agreed.