java.lang.NullPointerException (HelperAdapter)

getting some weird issue which is happening only in lower android versions like android 8 , 7.1.1, 7 when nesting models inside GroupModel.

`java.lang.NullPointerException at com.airbnb.epoxy.HelperAdapter.onCreateViewHolder(ModelGroupHolder.kt:272) at com.airbnb.epoxy.HelperAdapter.onCreateViewHolder(ModelGroupHolder.kt:252) at androidx.recyclerview.widget.RecyclerView$Adapter.createViewHolder(RecyclerView.java:7788) at com.airbnb.epoxy.HelperAdapter.createViewHolder(ModelGroupHolder.kt:265) at com.airbnb.epoxy.ModelGroupHolder.getViewHolder(ModelGroupHolder.kt:152) at com.airbnb.epoxy.ModelGroupHolder.bindGroupIfNeeded(ModelGroupHolder.kt:131) at com.airbnb.epoxy.EpoxyModelGroup.iterateModels(EpoxyModelGroup.java:223) at com.airbnb.epoxy.EpoxyModelGroup.bind(EpoxyModelGroup.java:136) at com.airbnb.epoxy.EpoxyModelGroup.bind(EpoxyModelGroup.java:61) at com.airbnb.epoxy.EpoxyViewHolder.bind(EpoxyViewHolder.java:68) at com.airbnb.epoxy.BaseEpoxyAdapter.onBindViewHolder(BaseEpoxyAdapter.java:118) at com.airbnb.epoxy.BaseEpoxyAdapter.onBindViewHolder(BaseEpoxyAdapter.java:20) at androidx.recyclerview.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:7847) at androidx.recyclerview.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:6646) at androidx.recyclerview.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:6917) at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6757) at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6753) at androidx.recyclerview.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2362) at androidx.recyclerview.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1662) at androidx.recyclerview.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1622) at androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:687) at com.airbnb.epoxy.stickyheader.StickyHeaderLinearLayoutManager.access$onLayoutChildren$s-991726552(StickyHeaderLinearLayoutManager.kt:29) at com.airbnb.epoxy.stickyheader.StickyHeaderLinearLayoutManager$onLayoutChildren$1.invoke(StickyHeaderLinearLayoutManager.kt:109) at com.airbnb.epoxy.stickyheader.StickyHeaderLinearLayoutManager$onLayoutChildren$1.invoke(StickyHeaderLinearLayoutManager.kt:29) at com.airbnb.epoxy.stickyheader.StickyHeaderLinearLayoutManager.restoreView(StickyHeaderLinearLayoutManager.kt:184) at com.airbnb.epoxy.stickyheader.StickyHeaderLinearLayoutManager.onLayoutChildren(StickyHeaderLinearLayoutManager.kt:109) at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:4645) at androidx.recyclerview.widget.RecyclerView.dispatchLayout(RecyclerView.java:4348) at androidx.recyclerview.widget.RecyclerView.onLayout(RecyclerView.java:4919)

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