Credit Card Dispute

[Blu350z]

Ok, so I work at a retail store and recently we have been receiving a bunch of credit card disputes, we check ids and everything. Purchases are being disputed about a month or 2 later after it was bought, even more. To me this seems fishy since they should have disputed the stuff around the same time since normal people check their credit cards and stuff almost everyday.

Or am I missing something? I never made a dispute ever, do you dispute something and takes the credit card a while for it to reported to the retailer or what?