Difficulty with nested if statments in Survey123

I’m new to this and having great difficulty with the below nested if statments. What I want it to do is:

1. If the user selected Periodic and Dropoff time or Collection time
   then produce the integer that the user chose from the
   periodic_speed_limit_low list.

2. If the user selected Periodic and Off peak time then produce the
   integer that the user chose from the periodic_speed_limit_high list.

3. If the user selected Fixed then produce the integer that the user
   chose from the fixed_speed_limit list.

if(selected(${speed_limit_type},'Fixed'),int(${fixed_speed_limit}),if selected(${speed_limit_type},'Periodic') and selected(${time_day}, 'Dropoff time') or selected(${time_day}, 'Collection time'),int(${periodic_speed_limit_low),if selected(${speed_limit_type},'Periodic') and selected(${time_day}, 'Offpeak time'),int(${periodic_speed_limit_high))

Can someone tell me why Connect isn’t accepting the above?