If you have their tv service, optimum will replace defective cable remote control unit at their store. Often you can use their remote to control tv functions, like power and volume.
Go to the Optimum store and they'll replace it, if it's their equipment. If it's the TV remote, take the numbers from the TV remote and search on Amazon and you can find what you need, cheap too. I replaced a lost vizio remote got the same one I had, new. $8.00. You'll find it.
For the cable Optimum will replace it at no cost to you. If it's for your TV itself try Ebay before Amazon. Do not get one from the manufacturer unless you haven't any choice. I purchased a remote for a television that was given to me by a friend, but they lost the remote. I called the manufacturer and they wanted $85 for it. Amazon wanted $65. I purchased it on Ebay for $9 and it looks exactly like the manufacturer's remote and works perfectly. I have had it for a year and it's the kids television in the family room, so it gets a lot of abuse. But I've not had any problems with it. My advice is definitely Ebay. Good luck.
If it's for the cable box call optimum. If it's for the TV I suggest Amazon.com
Amazon.com
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