Hi Cas and welcome to TrustedHousesitters and the community here in the forum. This is a great place to get advice from other members on topics such as these when new to the platform. You’ll likely get some good tips on this topic as we all have different ways to approach applying for sits.
Obviously we always hope that owners and sitters will maintain high levels of communication and reply in a timely manner, and there’s lots of help on the website for new members, but there’s no requirement to respond in a particular timeframe. Some are simply slower to respond, or might have have work or other commitments that mean they don’t check their account immediately or for a few days. It’s rare for people not to read at all, but very occasionally it can happen. Some will wait for several applicants before reviewing, others get back very quickly or let you know they are in the process of reviewing profiles.
There is nothing to prevent you from applying to more than one sit if you want to, although it becomes more difficult to manage if you apply to too many in one go. As sitters ourselves, our own approach is to apply for a sit, like you have, and wait three to four days. If no response and we have seen another sit we want to apply for, we send them a quick message checking they’ve seen our message. If still no reply we move on.
If we apply for another sit and get accepted, as a matter of courtesy from your side we write to say we are sorry, but we are withdrawing our application as we have been offered an alternative sit. We’ve done this sometimes to hear that the owner didn’t realise how quickly they need to get back, so it helps them better understand the process too.
24 hours isn’t long so I’d wait a little longer in case they’ve been away over the weekend, but if it remains unread, and you see another opportunity that works for you also, do apply. Good luck, and we hope you get accepted for that first sit very soon!