oda_api.disp.get_list_images_angular_distance fails for large time span

[ferrigno]

{'e1_kev': 28.0,
'e2_kev': 40.0,
't1': '2012-01-01T00:00:00',
't2': '2019-06-30T23:59:59',
'instrument': 'isgri',
'ra_ref': 299.5903154166666,
'dec_ref': 35.20160666666667,
'r': 1.0}

For these parameters, it fails, buut if I set t2=: '2015-06-30T23:59:59' it works