ANSWER:
You MUST ignore this waswas, do the wudu once and just move away from the washbasin. Don’t let Satan have a field day at your cost, you’re making him laugh his head off by spending so much time for wudu. You must defeat him. You should ask someone to stand while you’re doing wudu everytime. You must not do it alone or in the washroom, locking yourself up, this will make satan play with your mind. When someone is standing and watching you do wudu, you would feel embarrassed to keep repeating it and in sha Allah, with the leave of Allah, you would be rid of this OCD very soon.