When pnp people picker is used in SPFX, it is not giving suggestions.
Getting below error in network tab.
Microsoft.OData.Core.ODataException"
"A null value was found for the property named 'SharePointGroupID', which has the expected type 'Edm.Int32[Nullable=False]'. The expected type 'Edm.Int32[Nullable=False]' does not allow null values."
There is a bug in current version, You can try using beta. Full thread about it can be found here:
https://github.com/pnp/sp-dev-fx-controls-react/issues/1292