Two empty Calor gas bottles Knebworth (Knebworth SG3)

I have two empty Calor gas bottles. One 13kg and the other patio gas.
I have tried to return these to Calor gas but they won’t take them so someone can have the benefit of an empty bottle to take along to swap for a full bottle and then you only have to pay for the gas and not the £30 bottle deposit.

Please let me know if you want one or both and also when you are able to collect -Knebworth
Happy freegling.