Closing Fiscal Year company

I am not understanding this issue.  I have companies with fiscal years, my recent is 5-31-26.  When I go into June, to work with items in June, the files for January thru April are missing, they are gone, customer support says I have to complete May "totally" before I can go into June, how am I supposed to work in the month, I have answered the question, do you want to close the g/L, I say "no", cuz i am not done with May, but it will not take me to June, it just stalls.  If I do answer "yes", then I lose everything I have entered, reconciled and input I have done in 2026. I have used this software for 25 years and have NEVER had this issue.  Are we all going to have these issues at year end? We can't go into January until we are completely done with December, well a business cannot work on those terms.  I need to talk to someone, that understands my issue, the 2 people I have spoken to are trying to do the job, but I am not getting the answers to my questions.  Any emails or phone numbers someone can get to me, so I can speak to someone with higher authority or knowledge of how this program works?  I am just beyond frustrated.  Please can someone help me? Than