Hello Muneera,
In the catch block try assigning using mixed node.
Eg:
cr_mixed_node_tv TYPE REF TO cl_bsp_wd_mixed_node.
'
'
'lr_current = lr_iterator->get_first( ).
'
'
TRY.
lr_entity ?= lr_current.
CATCH cx_root.
cr_mixed_node_tv ?= lr_current.
lr_entity ?= cr_mixed_node_tv->if_bsp_wd_ext_property_access~get_model_node( ).
ENDTRY.
Hope it helps,
Regards,
Ashik