It appears that the positioning of subtitling is determined by the broadcaster, not by the TV set:
https://www.bbc.co.uk/reception/questions/everything-else/why-are-my-subtitles-blocking-programme-information-and-names
Googling suggests that Samsung sets do have a facility for overriding the broadcaster's default setting but that Sony ones don't.
However, if such an option is actually available on Sony sets (which, to be honest, I doubt) it should be among the settings for subtitling. How you access those settings will depend upon the exact model of your TV set. Once you've selected 'Settings' though, it's likely to be one of the following paths:
https://i.postimg.cc/htcLdmqc/Sony-Bravia.jpg