Take a look at apps like Watomatic ( apt.izzysoft.de/packages/com.p…) which send an auto-reply to inform the sender to better contact you at e.g. @signalapp (that auto-response-message could include hints like you check WA only weekly, but Signal promptly 😉 – so then stick to it: answer on Signal promptly, and ignore the WA messages for a few days at least, unless real urgent)