I gave a new job the reference of where I did work experience and I let them know I only did work experience there for a month and they said it was fine but then they sent them a form saying they had to know me for longer than 6 months. I don't get it?
You should contact them and ask for clarification on the criteria for a reference. Mention to them that they previously said it was fine for the reference to have only known you for 1 month, but now they're saying it has to be 6 months. Ask them to specify which one it is so you can get the correct reference to them. Sounds like whoever told you it was fine was incorrect.
My teacher was supposed to do it but she didn't so I contacted them and gave them my work experience contact details and they said they would send it to them. In my interview I told them I only did work experience for one month. So I don't think they connected the dots but they didn't give me any criteria for a reference they just asked for a reference.