Change dotplot labels from EnsemblID to geneID

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I have an AnnData object:

print(adata)

AnnData object with n_obs × n_vars = 77430 × 1988
obs: 'CONDITION', 'input.path', 'experiment', 'Sample type', 'BiOmics Sample Name', 'PatientID', 'SampleID', 'Response', 'Respond', 'Response2', 'Adjuvant', 'CIT', 'CIT2', 'Lesion2', 'Lesion', 'Stage', 'Fresh', 'CD3IHC', 'CD3IHC_RICZ', 'Mutation2', 'Mutation', 'Site', 'Age', 'Gender', 'PBMCs', 'PBMCs2', 'Seq samples', 'Quality', 'n_counts', 'n_genes', 'percent_mito', 'n_cPg', 'n_cPg2', 'batch', 'louvain'
var: 'symbol', 'n_cells'
uns: 'louvain', 'louvain_colors', 'neighbors', 'pca'
obsm: 'X_pca', 'X_umap'
varm: 'PCs'

To label the dotplot with gene symbols instead of ensemblID (index column) I use the gene_symbols parameter:

sc.pl.dotplot(adata=adata, var_names = ['ENSG00000104814','ENSG00000043462'], gene_symbols='symbol')

But I get the following error:

Error: Gene symbol 'ENSG00000104814' not found in given gene_symbols column: 'symbol'

TypeError Traceback (most recent call last)
in
4 sc.pl.dotplot(adata, myg, groupby=condition,dot_min=0,dot_max=0.2,vmin=0,vmax=0.2, save=title+'_'+myg_geneID+'.png')
5 if type(myg_geneID_orig) == list:
----> 6 sc.pl.dotplot(adata, myg, groupby=condition,dot_min=0,dot_max=0.2,vmin=0,vmax=0.2, gene_symbols='symbol', save=title+'_multiple_genes'+'.png')

/pstore/apps/bioinfo/scseq/modules/software/Scanpy/1.4.1-foss-2018b-Python-3.7.1-2018.12/lib/python3.7/site-packages/scanpy-1.4.1-py3.7.egg/scanpy/plotting/_anndata.py in dotplot(adata, var_names, groupby, use_raw, log, num_categories, expression_cutoff, mean_only_expressed, color_map, dot_max, dot_min, figsize, dendrogram, gene_symbols, var_group_positions, standard_scale, smallest_dot, var_group_labels, var_group_rotation, layer, show, save, **kwds)
1383 var_names = [var_names]
1384 categories, obs_tidy = _prepare_dataframe(adata, var_names, groupby, use_raw, log, num_categories,
-> 1385 layer=layer, gene_symbols=gene_symbols)
1386
1387 # for if category defined by groupby (if any) compute for each var_name

TypeError: cannot unpack non-iterable NoneType object

My understanding is that it should search for 'ENSG00000104814' in the index column and return the corresponding value in 'symbols', but it seems that is directly searching 'ENSG00000104814' in the 'symbols' column.

Thanks for helping, find below the version I am using:

Versions

scanpy==1.4.1 anndata==0.6.22.post1 numpy==1.15.4 scipy==1.1.0 pandas==0.25.2 scikit-learn==0.20.1 statsmodels==0.9.0 python-igraph==0.7.1 louvain==0.6.1

Start with scanpy.plotting._anndata.py, especially dotplot and its _prepare_dataframe call shown in the traceback. Reproduce the example with the AnnData var index and the symbol column, then trace how var_names and gene_symbols are matched. Done means dotplot accepts Ensembl IDs while displaying the corresponding gene symbols without the reported error.