Why our power apps no more accept the sharepoint field display names?

We have a power apps that was working well for 1.5 years. today some fields were not showing correctly, so i edit the power app and i noted that Power apps is raising errors on all the SharePoint fields which are been referenced by their display names. for example i am building this collections:-

Clear(colSource);
ForAll(StatuesForDashBoard, Collect(colSource ,Filter(
'Grant Applications',
IsGeneratedFromGrant = false && StaffMemberEmail = User().Email && ID = StatuesForDashBoard[@GrantApplicationID])
)
);
// Create a collection of all daily appointments
ClearCollect(
colGrants,
AddColumns(
ShowColumns(
colSource,
"ID",
"GrantTitle",
"Grantee",
"GrantAmountRequested_x0028_inUSD",
"Category",
"ApplicantEmailAddress",
"Areyouapplyingforthisgrantasanin",
"MailingAddress",
"StaffMemberEmail",
"RejectOnly"
),
"Level",
2
)
);
// Create a collection of all unique Title values
ClearCollect(
colGrantTitles,
AddColumns(
RenameColumns(
ForAll(Distinct(
colSource,
GrantTitle
), {Result: ThisRecord.Value}),
"Result",
"GrantTitle"
).GrantTitle,
"Level",
1
)
);
// Combine both collections into a single collection
ClearCollect(
colCombinedGrants,
colGrants,
colGrantTitles
);
//// *** NEW CODE ****
// Sort the combined collection
ClearCollect(
colSortedGrants,
SortByColumns(
colCombinedGrants,
"GrantTitle",
"GrantAmountRequested_x0028_inUSD",
"Level"
)
);

and i added the "colSortedGrants" as  the items for a gallery.

now previously i can reference a field which have a display name as "Are you applying for this grant as an individual?" and internal name as "Areyouapplyingforthisgrantasanin" using the display name.. but today this is no longer valid. here is a formula i am getting error on :-

now if i update the formula as follow it will work:-

any advice. if there is any recent update which force our app to raise these errors on display names?

Thanks