What should I do if my printing platform is dirty and bumpy?

When the build tape on the printing platform is dirty and damaged, the build tape needs to be replaced.First, tap "preheat" function in the equipment to heat the build plate to 60°-100° (high temperature is better,  60°is good to prevent burns ), keep it for a few minutes until the glue under the build tape softens, then remove the old build tape along the corner, and use alcohol to remove the residue on the build plate.After wiping up, put on the new build tape and smooth it out.