GE UltraFast Combo code 353 is usually associated with fabric softener residue in the lint filter. The check applies to the drying air circuit.
Separate the filter foam and mesh
The manufacturer documentation distinguishes the two parts of the lint filter. With the appliance turned off, remove it through the user access and separate the pieces as shown in the manual. Clean the foam and mesh using the approved method, without scraping them with tools or tearing the material.
A layer of product can restrict airflow even if there is not a large buildup of lint visible. Reinstall the parts in the correct orientation before using the Combo; do not run a drying cycle without the filter just to see whether it improves.
Assess the result
After cleaning, use the wash-and-dry check indicated by GE and note whether 353 appears again. If the filter is mounted correctly but drying is still abnormal, request service.
18 and Check and Clean Drain Pump Filter belong to the water circuit. The GE Appliances index helps distinguish them without assuming that every long drying time comes from the same filter.
Improvement should be observed with the complete filter assembly properly installed.