How to successfully replace an SSL certificate after it expires?

The certificate of the website is about to expire. How to replace the SSL certificate after expiration? Because I used to pay for it, but now I plan to use it for free, so I need to replace it rather than renew it. What can I do in this case? You can help me guide. This is the first time I have changed my certificate. I don't know how to operate it well. Thank you for your answers!

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Just find a free one and change it

 Corran wiring
Corran wiring · Clan Kelan Communication is a global supplier focusing on generic cabling. With more than 10 years of industry experience, it focuses on generic cabling products: copper cables, cables, distribution frames, cabinets, etc

There are both free and paid ones. Just find a technical replacement.

 Provincial Liquor - Chen Xiaobai _ Zero One Technology
Provincial Liquor - Chen Xiao · He is good at technical support such as SEO, inclusion and ranking, has been in the industry for 5 years, and has served as the deputy manager of inclusion and ranking in Guizhou Zero One Technology

Find me 15 meters directly

 No two weeks help
No two weeks help · Guangzhou Henglida, with 20 years of experience in customized production of storage shelves, specializes in customizing all kinds of heavy storage shelves and intelligent shelves

I use pagoda The panel is free. It is automatically renewed once every three months