@TheEnglishFlaneur I have sent you another DM with screenshots, let me know if you do not receive it.
Without going into specifics I can also assist you here.
If it is for the sit that you have recently applied for then the greyed-out dates you see when you view their listing means that the owner has reached the 5-application limit/the listing is paused and is reviewing the applications. Your application is still there, it just means others can not apply for those dates now.
To see the same applied for sit, scroll down your dashboard to the grey box ‘My House Sits’ and you can view the applied for sits here.
Let me know if you need any more help at all.