The dishwasher was full of soap suds but most of the water drain

Assuming someone has not put regular dishwashing detergent in the machine then suds is most commonly due to Rinse Aid liquid either being spilled in the machine, the top of the rinse aid dispenser is loose or leaking or over filled, least likely, the rinse aid dispenser is faulty. It will only affect one drawer as they are independent of each other. Once you have corrected the problem, clean up what you can of the rinse aid within the machine and run repeated rinse only cycles to wash away any last residue.

Frequently sudsing will cause an overflow and a flood alarm (F1 code) try to avoid this as there's a good chance a flood will fry the mains circuit card located at the bottom of the machine. Before you try and mop up a flood, turn off and un-plug the mains cord. A hair dryer can be helpful to really dry it out. Hope this helps

Suds? If you use dishwashing detergent you shouldn't get suds. If a small amount of sink type dish soap is left on a dish before loading it into the dishwasher this can happen. I would use several rinse and drain cycles with the racks and dishes removed until the suds are gone.

Never use any type of liquid dish soap made for sinks. The same thing that makes suds in the sink will make even more in the dish washer.

Hope this helps!