tubing printing issue (a gap in circle, not continuous)

Hi,

I'm trying to print a branched tube (two thinner tubes connecting to a larger tube) with flashforge creator pro and found that the two thinner tubes were not continuous. To make it more clear, I attached a schematic of the issue. During each layer printing, theoretically, it should be continuous for each circle and finish printing one-by-one. However, there is a gap in both circles in each layer printing. Does anyone know how to fix the problem? I'll appreciate it.
Attachment 14112