Inform the new company about the same. And they might ask for proof of separation for the previous company along with last payslips and joining/latest increment letter.  
  
 For that you might submit the mail for your resignation acceptance, or portal generated mail for resignation.

Android engineer

Software Developer

New company is asking for my relieving letter, which i don't have and will be having by a week or two so .
What should be submitted in this case ?
My latest

New company is asking for my relieving letter, which i don't have and will be having by a week or two so .
What should be submitted in this case ?
My latest payslip+ joining letter ?
I left my previous company in oct mid, i have payslip of sept with me ..

Will that work ? 
Help me

Background verification documents