while creating a new sprint no sprint name comes in option drop-down This sprint comes after

Hi Team, we are trying to create a new sprint, just for your info we have finished sprint 9 and currently no sprint running but the sprint Backlog, and we have some stories in sprint backlogs. when we trying to create a new sprint with 2 weeks of interval, then we are not able to select previous sprint name in option "This sprint comes after" and if we create a sprint it automatically taking sprint due date as 22 may. it is very strange,  we already tried to select manual date also but it again changing due date from may 22. Can anybody help us. Thanks and regards Ashish
1 answers

there might be problem in previous sprint creation can you may be share the snap shot of drop down of sprints