PBS Dependent to FLR(m) Immigration Health Surcharge

[liuk2]

Hi Experts,

We have landed ourselves in quite a unique situation and can't seem to find the answer online, so could someone please help us with the below query?

My wife has applied to switch from PBS Dependent to FLR(m) now that I have been granted ILR.
For her PBS dependent visa, she paid Immigration Health Surcharge for the period covering October 2017 to March 2019.
When filling the FLR(m) form online, we entered the previous IHS reference number instead of paying for a new one.

We have now obtained a new IHS reference number for 2.5 years (£500)

There is no option on the gov.uk website to edit IHS details.

Questions is:
Should we leave it as it is and attend the appointment with a cover letter?
Should we cancel the application and make a fresh application. THis will mean we will lose our appointment slot.

Many thanks.