If you mean you have 2 unpaid item cancellations in the past 12 months, whether you can bid, offer, or buy depends on the seller you are trying to buy from. Some don't enable that Buyer Requirement (block) at all. Some enable it but at more lenient parameters than the strictest level of blocking anyone with 2 in the past 12 months (some leave it at the defaults which are the lowest number for each parameter--2 strikes in the past 1 month--some long-time sellers haven't updated it from the old maximum timeframe of 6 months, and some for whatever reason choose to give more than second chances--the choices go up to 100 strikes in the lookback period).
So for the strictest level you will no longer be blocked by any seller (for that reason anyway) 12 months (and 1 day) after your second to last strike was issued (I know eBay no longer uses that term but it's a lot easier to type and comprehend than what the PR types decided eBay would call it). For those who don't have it set you can buy right now (assuming no other issues, such as running into your buying limits or another Buyer Requirement by that seller). For any other combination of x strikes in y months they will not apply to you when your xth to last strike is older than y months.
