My switch Minecraft won't let me play split-screen on the TV, but it works on handheld, it says "To play split-screen online, all users must have an online membership," because my sister tried to join me online when she doesn't have an online membership.

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However, this issue is Invalid.

This is a technical support issue; this site is for bug reports only. We do not have the resources to provide you with technical support.

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Thank you for your report!
However, this issue is Invalid.

This is a technical support issue; this site is for bug reports only. We do not have the resources to provide you with technical support.

Quick Links:
📓 Bug Tracker Guidelines – 📧 Mojang Support
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki