Dog with hip dysplasia

Hello, I have a dog with hip dysplasia he was diagnosed one year ago at the time I was unsure what the issue could be since he could move pain free. But it would only hurt if he was resting then tried to move. Anyways I took him to the vets, and they did an x-ray on him and concluded that he had hip dysplasia, they gave him a shot of librela, and some pain meds for 5 days. He was completely pain free after this and I tried to train him as much as possible I would walk him to the sea where he could swim everyday I did this everyday through the summer, he has been healthy for one year but a couple of days ago it started again. Do I need to go to the vets and get him another shot? What sort of training should I be doing with him dos and don'ts? Forgot to mention he is 3 years old and is an Amstaff x American bully xl mix. He weighs 34 kg. Picture of his x-ray

Hello - hip dysplasia is a chronic issue.  If your dog has hip dyplasia now, they will have it next month and next year and hopefully as an old dog.   It is therefore likely that your vet expected the pain to recurr.  I would ask them to assess your dogs' response to treatment and to discuss how things are best managed going forward.  I could make reccommendations, but your vets will need to choose a treatment appropriate to the patient, situation and condition in front of them.  Any drug is tested for use in particular circumstancs and it is important to appropriately match the drug to the circumstances.  The 'rules' for each drug are laid out in the data sheets, the folded paper of dense text that comes in the packaging of any drug.   I hope that you and your vet can find a satisfactoy regeim to keep your dog confortable going forward.