What make, model, and year is your rv? Does it have a battery disconnect switch? On travel trailers, there is usually a circuit breaker in the positive line, usually near the battery/tongue area. It may be hanging in midair, mounted to the frame, or in a junction box. It may need to be reset or replaced. It looks like this:
https://www.delcity.net/store/12V-Circuit-Breaker--Auto-Reset/p_198669.h_198846.r_IF3003?mkwid=5UmHNSEp&crid=11472933143&msclkid=320d44cdb4611687a11e1f057733a716&utm_source=bing&utm_medium=cpc&utm_campaign=Shopping%20-%20PLA's(BSC)&utm_term=4577198187950659&utm_content=Ad%20group%20%231