SAPUI5 oData requests with 2 question marks

[anatoli]

I have an application with mock server.

All requests supports utf-8

// mockserver.js part
var fnResponse = function (iErrCode, sMessage, aRequest) {
    aRequest.response = function (oXhr) {
        oXhr.respond(iErrCode, {"Content-Type": "text/plain;charset=utf-8"}, sMessage);
    };
};

If i send some data to dackend with only 1 question mark

test?

then after data update i have still test?

But by send of test?? i receive test something like testjQuery223039144209666350105_1579678479568

by send of five question marks, the first to changes to jQuery... and other 3 are still in text.

How can i solve it?