iOS App for Export Text Messages

Hello Friends,

Can anyone please tell me if they know of an iOS App or method that I can use to export text messages?

I am using an iPhone 8 Plus and an iPad Pro, both are on iOS 13.4.

Unfortunately I do not have access to a PC or Mac which is why I am hoping to find an App or other method for doing this.

Lastly if it were possible I would just screen shot them, but in my case I have to export nearly 5 months worth and that method of course would take a long long time.

Many thanks in advance for your advice and time. Thank you.