Certainly is.
This was clearly so persistent that it caused the software to degrade in performance, and your negative feelings probably made the dry spell seem like the casino was cheating.
Getting you to deposit again would only tie you into further WR, and you would most likely find the bonus was non-cashable anyway, so should not be taken, as you cannot win it.
Clearly, once you reached zero, there was no longer any point in further baiting this trap, so you just got offered 50%, and this was at a time where, for once, the 200% became worth taking.
Rather than closing the pop-up, try moving it away from your game to the bottom of the screen, where they can chat to themselves. They will not be able to relaunch the window since it is still up, but neatly out of the way.
Empty Fruities Astern Capt'n
Back to port for unloading.
Full Sails - before we get raided ourselves.
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