• use 8 or more letters
• include upper-case and lower-case letters
• use at least 1 symbol: !@#$%^&*
• not use the same character 3 times in a row, for example, AAA

You can't reuse old passwords or change your password twice in 24 hours. Your password maybe rejected if it includes personal details, common words or phrases, predictable patterns like '12345'.