land exchanged verbally

Santlal the owner of roadside property and backyard side ,transfer the roadside property to Ram in 1980. Z the son of Santlal didn't agree the deed and construct the house on the same land which is on roadside. Santlal manage to agree Ram that my son Z will live on this land. Ram told his son S,T,U,V that never disturb Z living on this land. In 1991 Santlal again written the same roadside land to his son Z on his name. Santlal in return given backyard property to Ram in 1980. Santlal died in 2006 and Ram died in 2008. Since 1980 Z is residing in this property happily. They have constructed kaccha house in 1980 and again in 2010 they have renovated the house. They also do cropping on the same land. They also had planted many trees on the land. Now in 2021 S,T,U,V is asking the land from road side. In 2011 S,T,U,V have given the backyard land number 21 on mortgage to Z and and is still on mortgage. But point to be noted that land number 22 which is on road side is on name of Ram and land number 21 which is on backyard is on name of Santlal. Since 40 years S,T,U,V didn't have any problem but now they are claiming land number 22. S,T,U,V is breaking his father's promise that not to disturb Z in future. S,T,U,V is saying that my father has told Z to live on this land but now we are the next generation and we want our property. Now please suggest some remedy. Is it possible that S,T,U,V can claim that land or Z will the owner. Please suggest if the case is filed who will win the case S,T,U,V or Z. Can adverse possession can be applied in this case?