You need to provide more detail.
Where are the adult dependents based?
How old are they?
What other family live in their country of residence?
Do the adult dependent relatives meet the onerous requiring care criteria and if so, why is the care not affordable in their home country?
immigration-for-family-members/adult-de ... 87771.html
What were the reasons for refusal?
What is your UK immigration status if you were the sponsor?
Has the adult dependent relative visited the UK before and if so, how long for each visit and how often?
Appeals are rarely successful. This is the most difficult visa to get since the rules were tightened in 2012.
An ADR refusal also shuts the door to any future visitor visa applications.