Hi there.
Believe me, you are most certainly not the only one in this situation but you do have some work ahead of you to get CRA off your back and correct your tax situation.
You say that you spoke with a CRA agent and registered the GST/HST number. Do you know if the actual GST/HST return get filed for 2021 and 2022? The GST/HST is filed separately from your personal income tax. It would depend on how CRA filed the return if you need to amend 2021. How many years back, depends on how many years you were over $30,000.
Please be aware that if you have not filed your HST return you will be charged a late filing fee as well as interest.
On the other side of things though you are able to deduct the HST that you pay on your expenses to offset the GST/HST that you charge on your sales. So for 2022 when you calculate your expenses be sure to calculate the GST/HST that you paid on all your expenses.
You say that this correspondence from CRA was relating to 2021; have you been collecting HST for 2022? Once you are registered for GST/HST you have to always collect HST on your sales even if less than $30,000 in a given year. That means that for 2022 you will have to account for GST/HST on your sales.
I know there is a lot of information in this reply. My suggestion to you is to hire some profiessional help with this in order not to be on a bad start with CRA for your business. Turbotax offers a service for self employed people whhere they can get live expert help and may be able to guide you further without having to pay the big fees an accountant will charge.
My final piece of advice is if in the event that you have a GST/HST return that is due and you cannot make the payment, make sure the return gets filed ontime. That way you will avoid the larger pentalty for filing late.
Feel free to ask any additional questions. Best of luck.
