Asics sending me payment requests to my paypal after sending me shoes without chargin

Strange story...

I bought a pair of trainers from Asics GB website that was £150
I saw a transaction on my Paypal account for £120, I didn't recognize it right away as it did not say Asics and I hadn't bought anything costing £120 so I contacted paypal about this unknown transaction.
Paypal refunded me and blocked the merchant.
I then coincidentally bought another pair of Asics trainers and both pairs were sent out without me being charged.

I contacted Paypal to tell them I now knew it was Asics that took the £120 as it turned out I already had £30 in my account which made the transaction show up as £120 so paypal did not think I purposely lied to them and that they could go ahead and recharge the order(s)
Paypal said not to worry, the merchant will request the money again.
I did not hear anything about either order for months, but then asics sent me a few Paypal payment requests for my "Unpaid order" that I just declined.
They seemed to have given up now though.

I am cool to not pay them?
&
Am I OK to buy off the Asics website again?

Thank you