Thank you for contacting us, and sorry for the issue you're experiencing here. We have seen this before, but we don't know what causes it to happen. However, I believe the fix should be pretty easy. Go ahead and open the settings for mSecure on either your Mac or your iPhone, then disabled syncing altogether in the Sync Settings screen. Next, go ahead and reinstall mSecure on your iPad and sign in to the account. There will be no data, and that's ok for now. Now, on your Mac or iPhone, turn mSecure Cloud syncing back on.
After about two minutes, does the data get synced over to your iPad?