I can't save the plan preferred training days either on my watch (Enduro 3) as there is no UI for it, on my mobile as the Save button does not do anything and exiting the dialog simply discards the changes, and on the web because it redirects me to the following URL with a blank page:
https://connect.garmin.com/modern/training/adaptive/details/edit/workout/41127962/undefined
Console errors at the moment of redirections:
index__vendor__5.14.3.1.js:4 TypeError: Cannot read properties of null (reading 'find')
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1050
at Array.map (<anonymous>)
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1033
at Object.useMemo (index__vendor__5.14.3.1.js:4:674655)
at index__vendor__5.14.3.1.js:4:849839
at B (9301.53a4c3dc.chunk__5.14.3.1.js:3:1025)
at Aa (index__vendor__5.14.3.1.js:4:668287)
at ws (index__vendor__5.14.3.1.js:4:727938)
at yc (index__vendor__5.14.3.1.js:4:717044)
at vc (index__vendor__5.14.3.1.js:4:716972)
at Ac (index__vendor__5.14.3.1.js:4:716835)
at ic (index__vendor__5.14.3.1.js:4:713615)
at oc (index__vendor__5.14.3.1.js:4:712166)
at _ (index__vendor__5.14.3.1.js:4:888106)
at MessagePort.S (index__vendor__5.14.3.1.js:4:888640)
(anonymous) @ index__vendor__5.14.3.1.js:4
14:57:32.736 index__vendor__5.14.3.1.js:4 Uncaught TypeError: Cannot read properties of null (reading 'find')
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1050
at Array.map (<anonymous>)
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1033
at Object.useMemo (index__vendor__5.14.3.1.js:4:674655)
at index__vendor__5.14.3.1.js:4:849839
at B (9301.53a4c3dc.chunk__5.14.3.1.js:3:1025)
at Aa (index__vendor__5.14.3.1.js:4:668287)
at ws (index__vendor__5.14.3.1.js:4:727938)
at yc (index__vendor__5.14.3.1.js:4:717044)
at vc (index__vendor__5.14.3.1.js:4:716972)
at Ac (index__vendor__5.14.3.1.js:4:716835)
at ic (index__vendor__5.14.3.1.js:4:713615)
at oc (index__vendor__5.14.3.1.js:4:712166)
at _ (index__vendor__5.14.3.1.js:4:888106)
at MessagePort.S (index__vendor__5.14.3.1.js:4:888640)
14:59:01.874 o430870.ingest.sentry.io/api/5591783/envelope/?sentry_key=f0377f25d5534ad589ab3a9634f25e71&sentry_version=7&sentry_client=sentry.javascript.react%2F7.120.3:1
Failed to load resource: the server responded with a status of 429 ()
14:59:10.234 index__vendor__5.14.3.1.js:4 TypeError: Cannot read properties of null (reading 'find')
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1050
at Array.map (<anonymous>)
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1033
at Object.useMemo (index__vendor__5.14.3.1.js:4:674655)
at index__vendor__5.14.3.1.js:4:849839
at B (9301.53a4c3dc.chunk__5.14.3.1.js:3:1025)
at Aa (index__vendor__5.14.3.1.js:4:668287)
at ws (index__vendor__5.14.3.1.js:4:727938)
at yc (index__vendor__5.14.3.1.js:4:717044)
at vc (index__vendor__5.14.3.1.js:4:716972)
at Ac (index__vendor__5.14.3.1.js:4:716835)
at ic (index__vendor__5.14.3.1.js:4:713615)
at oc (index__vendor__5.14.3.1.js:4:712166)
at _ (index__vendor__5.14.3.1.js:4:888106)
at MessagePort.S (index__vendor__5.14.3.1.js:4:888640)
(anonymous) @ index__vendor__5.14.3.1.js:4
14:59:10.236 index__vendor__5.14.3.1.js:4 Uncaught TypeError: Cannot read properties of null (reading 'find')
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1050
at Array.map (<anonymous>)
at 9301.53a4c3dc.chunk__5.14.3.1.js:3:1033
at Object.useMemo (index__vendor__5.14.3.1.js:4:674655)
at index__vendor__5.14.3.1.js:4:849839
at B (9301.53a4c3dc.chunk__5.14.3.1.js:3:1025)
at Aa (index__vendor__5.14.3.1.js:4:668287)
at ws (index__vendor__5.14.3.1.js:4:727938)
at yc (index__vendor__5.14.3.1.js:4:717044)
at vc (index__vendor__5.14.3.1.js:4:716972)
at Ac (index__vendor__5.14.3.1.js:4:716835)
at ic (index__vendor__5.14.3.1.js:4:713615)
at oc (index__vendor__5.14.3.1.js:4:712166)
at _ (index__vendor__5.14.3.1.js:4:888106)
at MessagePort.S (index__vendor__5.14.3.1.js:4:888640)