Head lining

Below pictures show how, due to the dehumidifier being switched off, condensation has caused the edges of the headlining vinyl to come out of the gripper rods on both sides of the saloon. We’d be grateful to know if anyone else has found out how to tuck the vinyl back inside the gripper rods!  We’ve tried heating the fabric and the rod but it soon cools down and won’t clip back with the vinyl tucked in, though the empty outer rod clicks into place with no difficulty. We don’t want to replace the whole lining as the rest of it is very neat and in good condition.