Unexpected Tax increase

[Goldenhandshake]

Hi, despite there being no changes to my salary, tax code or deductions this month, my income tax has increased by over £100, does anyone have a clue why? Waiting on a response from my payroll provider but wondered if anyone here knew a possible reason? Seems so random.

[FlabulousChic]

Has your tax code changed? You can ring hmrc id it has as you are supposed to be noticed yourself. Is this a new job this year or recently?