Deleting a project

if(a!isNullOrEmpty(fv!row['recordType!AX Vehicle.fields.image'])
,a!EXAMPLE_DOCUMENT_IMAGE(),
fv!row['recordType!AX Vehicle.fields.image'])

Hello Appians
I am new to Appian and following the Appian developer learning path I faced an error in "write a maintenance record" of the process model, tried to solve it but in the end, I deleted the project and started a new one and now I am facing this error

"Error Evaluating UI Expression Expression evaluation error at function a!gridField [line 51]: A grid component [label="null"] has an invalid value for "columns". A grid column [label="Image"] has encountered an error. Expression evaluation error at function a!imageField [line 51]: Invalid Content ID"

this error shows up once I add a new Document Image column in the list of the vehicle record type 


and for some reason, the Acme Auto Solution Application already built has the same error 
So I guess the problem is not from the expression or the record type Can anyone please help?