Your reservoir seems to be loose (uncemented) sand. This is a difficult case, because  the only cement in uncemented sands is ...  water. The irriducible water saturation that represent the thin film of water coating the sand grains can act as a very weak "cement" between sand grains.

If the oil flow is slow, the pressure differential between the formation and the borehole is small and no water is produced alongside the oil, the sand ingression in the borehole is minimum or trascurable.

If the oil velocity is high, the pressure differential is high and most importantly if there is some formation water produced with the oil, then sand ingression becomes unstoppable. This is somehow like wet sand collapsing on the sides of a hole digged by children on the beach near the sea shore to a depth slightly deeper than the water table (one or two feet deep) when the percolating water fills the hole.

Probably, the most efficient remedy against sand ingression is to reduce the oil flow untill no formation water is produced with the oil. It can be too late now for such remedy, though.