Hi Barb@46,
welcome to the Apple (User-to-user) Community!
Re: Pairing (Signia) hearing aids with Apple Watch
Am no expert in this area, yet your questions surely deserve some response, and perhaps others will join in.
Wondering if your Signia Hearing Aids are on the list of "Made for iPhone" Compatible Aids (Link below) :
List of Made for iPhone hearing devices - Apple Support
If so, : Use Made for iPhone hearing devices - Apple Support has trouble-shooting tips at the bottom:
Eg: scroll to: "If you need help :
Try these solutions if your hearing device doesn't connect or work as expected."
The hearing aid manufacturer may have info. or instructions on their website, or maybe there is an app you can use : their Support Team may have relevant. information
You may want to contact the people who sold you the hearing aids, or your hearing professional, for any advice they can give.
In Apple Support's online article: Use hearing devices with iPhone - Apple Support
you can scroll to: "Use your hearing devices with more than one device" for tips.
There are non-Apple articles available online, like the one below that may or may not be helpful:
https://www.healthyhearing.com/report/53487-Using-your-hearing-aids-with-your-apple-watch
There are: Accessibility audio settings on Apple Watch - Apple Support
If needed: Apple's Accessibility Support Website
(NB: You can "Get Support" from the link at the bottom of their website:)
Accessibility Support - Official Apple Support
Hope something here is helpful to you :-)