Hi there, welcome to the forum
I use to have a boxer named Lennox too

and like your lennox, house training him was a very long...long process. We just had to be vigilant with him, out every two hours no matter what. It took months and months, but he did eventually get it.
I would also take treats outside with me to give him when he did his business.
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tie - 12-year-old flashy brindle male
Newman - 2 Year Old flashy Brindle male
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