Expired permesso di soggiorno

I am a student and  my permesso di soggiorno has been expired , while I still had an active work contract with my employer. It got expired 5 May 2023. Now that my work contract is over. I am waiting for my new contract this season ,so I can convert and renew my permesso to work visa.My employer is also willing to help me  by providing me a residence letter to help me proceed with my documentation , but i am worried about the procedure if all of the formalities didn't work,Since my permesso has been expired. I would appreciate,  if I could get some assistance from you guys .please help me.