User Profile

I'm implementing the v2 server notifications, according to responsebodyv2 documentation , "The signedPayload is a string of three Base64 URL-encoded components, separated by a period.", however in all the notifications I got, there's a datetime value, which includes a dot, for example: "GRlRRWFJKUl2022-08-25T07:01:44.031817718Z", which brings the number of periods from expected 2 - to 3, and the number of expected string chunks to 4 instead of 3, can you please let me know what is the best practice recommended in this case? Do you search for a date time pattern and remove it before processing, or merge 2 chunks into 1, or I'm getting some not-normal notifications?