This is not normal.
I have not had this problem with any Garmln watch since 2016.
Also, the Garmin support articles describe that the CPE should be valid for 3 to 14 days :
„How Do I Check EPO or CPE Status?
EPO or CPE status can be checked under About in the System or Setup menu of your Garmin product.
EPO and CPE files expire, and are usually only good for a range of 3-14 days.“
All known and also support described methods to fix it do not help.
Reset, master reset, delete cpe.bin, delete remotesw folder.
12 hours after sync with CGM or Express, CPE is invalid.
Error remains.
The same behavior ON TWO watches of the instinct Solar series.
GARMIN PLEASE FIX THIS