尽管 + Verb (feel free to)

"Go ahead, feel free"

• despite尽管jǐn guǎn has a second use: "feel free to / go ahead and" (before a verb).
• to have / there is有yǒuquestion问题wèn tídespite尽管jǐn guǎnto ask问wèn = "if you have questions, feel free to ask."
• Here it gives permission, not concession ("although").

despite尽管jǐn guǎn + Verb

• despite尽管jǐn guǎn = "go right ahead" — no need to hold back.

have有yǒuquestions问题wèn tífeel free尽管jǐn guǎnask问wèn。

• to have / there is有yǒuquestion问题wèn tídespite尽管jǐn guǎnto ask问wèn = "feel free to ask if you have questions."

Recap

Read the full reference: HSK 5 grammar — Adverbs.