My fenix 5x is cutting off sections of my activity (looks like the gps disconnects). My watch is fully up to date. It is almost 6 years old.

I am sorry there is an issue. If researching your GPS course, you see your watch losing GPS acquisition more and more, you might not be able to resolve the behavior. If not a hardware issue with your GPS antenna, you might be able to resolve it.

Please try the following:

Soft Reset: Hold down your top left power button until your watch shuts off then let go of the button.

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