Sheep shearing is broken in 17.02 alpha. You can a sheer a sheep once with shears then, even when a sheep eats, you cannot shear them again unless you use a new shear.

This is a duplicate of MCPE-18533

Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-17480.

It has been linked to this report. If you have additional information, please add it to that report.

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