Hello @Gardengirl045 and a very warm welcome to the Community Forum 
As @Silversitters mentioned, we have also had exactly the same thing happen to us where we have had our application confirmed straight away and receiving a message saying we have been chosen for this sit. However before we confirm we always request a video call with them first, (which is our preferred form of contact), or at the very least a telephone call.
We also ask for their contact number at this point and provide ours and again as @Silversitters said, we also ask when would be a preferred time for them.
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