Clear retainers and aligners are cleaned with a toothbrush and soap. Don’t use toothpaste, because it contains fine polishing particles that scratch the surface of the retainer and make it dull. Besides spoiling the appearance of the retainer, a dull surface makes it easier for bacteria and stains to stick to it.
Aligner-type retainers should not be cleaned with warm water or exposed to high temperatures, because they lose their shape. You can use a cleaning tablet for aligners and retainers at least once a week to keep the appliance hygienic.
This answer is for general information. Your own case needs an examination by an orthodontist.