I use seam sealer glue.  Messy and kinda labor intensive, but it sticks well.

If you have never used this shit - be very careful. Getting it off is almost not happening!

Suggest carefully removing any tape that allows its' easy removal, then laundering the garments with the proper chemicals first, Rinse 2X, then de-grease areas to which tape will be applied with alcohol, allowing alcohol to completely dry before applying tape.  I think I would apply new tape over worn/missing seam-sealing tape and overlap sides of original tape by an inch or so; the fewer seams in the new tape, the better.  Allow tape to "set", possibly applying some fairly "gentle" heat to the tape post-application while using a small wheel to "roll-in" the tape for better contact. Many external "Sew-throughs" are best treated (post laundering) but prior to applying waterproofing chems, with water-based "seam-sealer", brushed into the stitching.  The reason for this step is to seal the stitching holes and the thread thus preventing water from entering the garment in the first place.

After things have settled for a couple of days or so, treat with appropriate waterproofing chems.  Done right, your garment will probably work pretty well, likely better than in a long time.  Get more DWR than you think you'll need.  You'll use it at some point in the future.

I used "SUNDELY Iron on Hot Melt Seam Sealing Repair Adhesive Fusible Tape Roll 0.86" X 16' (22mm X 5m) 3 Layer for Waterproof Fabrics Sportswear Ski Snow Gear" 2 years ago and it is still  holding.

I’d strip off all the old tape, clean the seams of all old adhesive with isopropyl alcohol, and use Seam Grip in the brush-type applicator.

Gear Aid repair tape.

Good stuff.  Adheres much more better with some gentle heat applied.