I'm wearing trays 30 and there is a gap between my two teeth with attachments and trays. Is this ok? (photo)

Since then the gap is there again for at least 3 last trays. I moved to another trays after 3 or more weeks when I felt like they were loose and weee not doing anything. I moved to EU and my doctor is in USA. He doesn't really give me any advice other then wear trays is there is a gap. My upper teeth fits perfect. Is there anything that can cause this problem?i have 2 upper wisdom teeth and one lower wisdom tooth. I also have one tooth crown on my second molar. Could that be the reason?