ヘレン レディース ナイトドレス

I prefer a nighty to be roomy so fitting up to a size 20 sounded good, as would usually upsize to an 18 on the high street. Although the body of the nighty was fine the arm holes were way too small and tight and I don't have large/fat arms
The cotton although nice quality was quite heavy for a summer nighty. Chose a couple of alternative styles for an exchange, both listed at fitting up to size 20 (Abigail and Jane) but was informed that these wouldn't be recommended either as they too came up small. Such a shame and so disappointed as thought I'd finally found what I was looking for, but opted for a refund.
Customer service were very helpful but didn't seem surprised that there were problems with sizing which leads me to think this might be a regular issue. More detailed and honest sizing on the website would save a lot of time and disappointment.