@may12345, I can understand your concern. You were likely told special instruction regarding bathroom usage for your father. But this was an unavoidable accident and he needed your help.

Over time, the radioactive injection changes into a non-radioactive form. Since this happened on day 2, there was already less radioactive material in your father's urine. You did the right thing to wash with soap and warm water right away.

I found this information in these instructions from U of Michigan to really helpful and clear:
https://www.med.umich.edu/1libr/radiology/PluvictoDischargeInstructions.pdf
Cleaning up, you'll want to wash your father's laundry separately from the laundry of other members of your household for 1 week. Wash his items at least twice using a standard washing machine. You do not need to use bleach and do not need extra rinses.
Wear disposable gloves (nitrile gloves are best) for at least 3 days after treatment when helping the patient go to the bathroom or when cleaning up vomit, blood, urine, or feces.

I also recommend calling your father's medical team to ensure there is no further action that you should take. Like I said, washing immediately was the best first action.

How is your dad doing now? Is he able to get to the bathroom more easily? How are you doing?