ase.io.cif.read_cif error

Hello,

reading in the cif from RCSB PDB - 6SX6: Guanine-rich oligonucleotide with 5'-GC end form G-quadruplex with A(GGGG)A hexad, GCGC- and G-quartets and two symmetric GG and AA base pairs (in order to export it xyz) I get
line 662, in read_cif
return next(g)
StopIteration

Does anyone now if I can do something about this?

Best