As you remember from where? First bans are usually 7 days but it depends on the circumstances and if you've had previous accounts banned then this is an appropriate punishment. I know you're protesting your innocence but a couple of other accounts that were brought up with yours look like they could belong to you (same style of posting and posting in the same giveaways one after the other on the same days etc) but this is just from my observation and BadBear has access to much more information than I do but he's usually spot on with this sort of stuff.

Your posts wouldn't be spam if you put this much effort into the rest of them. I suspect you have alt accounts you're not telling us about that have been in trouble for this before and this is the reason for the hefty ban.

If I had to guess I would say it is because of your paid signature plus at least two pages of insubstantial posts. The two pages I looked at are very short mostly two (very short) sentences that really do not add to the conversation.

If you are banned for 60 days this is most likely not your first ban