RuntimeError: The expanded size of the tensor (16) must match the existing size (63) at non-singleton dimension 0. Target sizes: [16]. Tensor sizes: [63]

please I used the function:

self.pool1 = TopKPooling(self.dimensions, ratio=0.8)

in the forward part of my class:

recon, edge_index, _, batch, _, _ = self.pool1(recon, edges, None, batch)

but after two epoches I get this error message:

--> 247         recon, edge_index, _, batch, _, _ = self.pool1(recon, edges, None, batch)

/usr/local/lib/python3.7/dist-packages/torch/nn/modules/module.py in _call_impl(self, *input, **kwargs)
   1108         if not (self._backward_hooks or self._forward_hooks or self._forward_pre_hooks or _global_backward_hooks
   1109                 or _global_forward_hooks or _global_forward_pre_hooks):
-> 1110             return forward_call(*input, **kwargs)
   1111         # Do not call functions when jit is used
   1112         full_backward_hooks, non_full_backward_hooks = [], []

/usr/local/lib/python3.7/dist-packages/torch_geometric/nn/pool/topk_pool.py in forward(self, x, edge_index, edge_attr, batch, attn)
    160             score = softmax(score, batch)
    161 
--> 162         perm = topk(score, self.ratio, batch, self.min_score)
    163         x = x[perm] * score[perm].view(-1, 1)
    164         x = self.multiplier * x if self.multiplier != 1 else x

/usr/local/lib/python3.7/dist-packages/torch_geometric/nn/pool/topk_pool.py in topk(x, ratio, batch, min_score, tol)
     19         perm = (x > scores_min).nonzero(as_tuple=False).view(-1)
     20     else:
---> 21         num_nodes = scatter_add(batch.new_ones(x.size(0)), batch, dim=0)
     22         batch_size, max_num_nodes = num_nodes.size(0), num_nodes.max().item()
     23 

/usr/local/lib/python3.7/dist-packages/torch_scatter/scatter.py in scatter_add(src, index, dim, out, dim_size)
     27                 out: Optional[torch.Tensor] = None,
     28                 dim_size: Optional[int] = None) -> torch.Tensor:
---> 29     return scatter_sum(src, index, dim, out, dim_size)
     30 
     31 

/usr/local/lib/python3.7/dist-packages/torch_scatter/scatter.py in scatter_sum(src, index, dim, out, dim_size)
      9                 out: Optional[torch.Tensor] = None,
     10                 dim_size: Optional[int] = None) -> torch.Tensor:
---> 11     index = broadcast(index, src, dim)
     12     if out is None:
     13         size = list(src.size())

/usr/local/lib/python3.7/dist-packages/torch_scatter/utils.py in broadcast(src, other, dim)
     10     for _ in range(src.dim(), other.dim()):
     11         src = src.unsqueeze(-1)
---> 12     src = src.expand(other.size())
     13     return src

RuntimeError: The expanded size of the tensor (16) must match the existing size (63) at non-singleton dimension 0.  Target sizes: [16].  Tensor sizes: [63]

How can I solve this problem? and thank you