If you can afford it (or this is a big enough issue that you need to do something), use a lawyer, particularly a strata lawyer. An initial consultation might be free or at a set cost, and they can give you a reasonable idea of your chances of success, and what needs to be done. Then if you engage them, they will handle it all for you. And they will give you the costs involved before you get very far. Remember that once a lawyer is involved all the interested parties take it a lot more seriously.
Or, since living in strata building means living in a community, then organise! On your own, you have fewer options and it takes more effort, than in a group. So approach your neighbours and check if the noise really isn’t disturbing them. Do you know your neighbours? If not, then this is a good excuse to remedy that. You can slip a (very polite) notice under everyone’s doors (include the recalcitrant resident, as someone will involve them anyway) saying that the noise of the barking dog in Unit XX is disturbing you, and ask if anyone also thinks so. If so, email me at XXXX – and then set up a group and have a Zoom meeting about it. Take the results to the strata manager, and point out that several people are upset. Make sure you are very polite, and very factual – keep in mind the problem residents will read it too. There’s a good chance that once the recalcitrant dog owners realise that the building is organising against them, they will take things more seriously.
You can take this further. Visit the strata manager and make a copy of the strata register, with all the owners emails and details. If the dog owners are renting, then send a very polite email to the owner or their agents, explaining how the barking dog is distressing you. (Renters need the owners permission to keep a dog, and not all obtain this). Contact the owners as well as the residents… Point out that the barking dog devalues their units, and could drive tenants away… Organise, but be nice about it.
If nothing else, a problem shared is a problem reduced. And you will probably make some allies, for the next issue that crops up in the building…