It is always recommended that you personally sign in and out with your on-site manager before/after your shift. If you have any issues clocking-in or out on the app, make sure you contact the hiring manager with the corrected time. Hiring managers use Clock-In/Out to verify your hours, and without having that information it could raise issues and delay payments.
You can always send your hiring manager a message in the Jobble Chat. If you prefer to reach your hiring manager directly, you can find their contact information in your acceptance email titled: “You're Hired! Your Application Has Been Accepted.”