Medical insurance caused change in tax code

Hi, Received this notice your Medical insurance has been increased from £201 to £842 your Other items has been increased from £37 to £40 we estimate you have underpaid £68 tax this year But I'm a little confused buy it all, firstly my employer benefits me private medical and I pay an additional monthly premium for my wife. She did recently receive medical care which she paid the excess on. Is that where the £842 comes from and every time we use the private medical I will have to pay additional tax? Secondly it's a £68 deficit, but my PAYE went up £30 this month, surely I should be allowed to clear the remainder rather than pay £30 additional until April? Apologies for all the questions, it's just very confusing.

Hi,

As we would need to access your records to answer your query, you will need to contact our Income Tax ream for advice.

Income Tax: general enquiries

Thank you.